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2010 PONTIAC G5 Service Repair Manual .pdf



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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

2009 ENGINE
Engine Mechanical - 2.0L - Cobalt & G5

SPECIFICATIONS
FASTENER TIGHTENING SPECIFICATIONS
Specification
Application
A/C Compressor to Block Bolt
Balance Shaft Adjustable Chain Guide Bolt
Balance Shaft Fixed Chain Guide Bolt
Balance Shaft Retaining Bolt
Block Coolant Plug
Block Heater Bolt
Cam Cover to Cylinder Head Bolt
Cam Cover to Ground Cable Bolt
Cam Cover to Ground Cable Stud
Camshaft

Metric
22 N.m
10 N.m
12 N.m
10 N.m
15 N.m
10 N.m
10 N.m
10 N.m
10 N.m

English
16 lb ft
89 lb in
106 lb in
89 lb in
11 lb ft
89 lb in
89 lb in
89 lb in
89 lb in



Camshaft Cap Bolt

10 N.m

89 lb in



Camshaft Position Actuator Solenoid Valve Bolt

10 N.m

89 lb in



Camshaft Position Sensor Bolt

10 N.m

89 lb in



Camshaft Timing Chain Tensioner

75 N.m

55 lb ft



Exhaust Camshaft Position Actuator



First Pass

30 N.m

22 lb ft



Final Pass



Intake Camshaft Position Actuator



First Pass

100 degrees
30 N.m
100 degrees

Final Pass
Catalytic Converter Stud
Chain Guide Access Hole Plug
Charger AIR Bypass Bolt
Charger AIR Bypass Nut
Connecting Rod Bolt




22 lb ft

First Pass

50 N.m
90 N.m
25 N.m
25 N.m

37 lb ft
59 lb ft
18 lb ft
18 lb ft

25 N.m

18 lb ft
100 degrees

Final Pass
Coolant Jacket Plug


35 N.m

26 lb ft

Microsoft
Tuesday, May 18, 2010 1:01:25
1:01:00 PM

Page 1

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Crankshaft Balancer Bolt


100 N.m

First Pass

125 degrees

Final Pass
Crankshaft Bearings - Lower Crankcase to Block - Bedplate




20 N.m

First Pass

First Pass

15 N.m
10 N.m

11 lb ft
89 lb in

30 N.m

22 lb ft
155 degrees

Final Pass
Cylinder Head Front Chain Case Bolt
Cylinder Head Oil Gallery Plug
Cylinder Head Opening Plate Bolt
Drive Belt Tensioner Bolt
Engine Coolant Temperature Sensor
Engine Lift Bracket Front Bolt
Engine Lift Bracket Rear Bolt
Engine Mount to Intermediate Bracket
Engine Mount to Midrail Nuts
Exhaust Manifold Heat Shield Bolt
Exhaust Manifold to Turbocharger Stud
Exhaust Manifold to Cylinder Head Nut
Exhaust Manifold to Cylinder Head Stud
Flywheel Bolt - Automatic Transmission




First Pass

30 N.m
35 N.m
10 N.m
45 N.m
20 N.m
25 N.m
25 N.m
65 N.m
100 N.m
25 N.m
10 N.m
14 N.m
15 N.m

22 lb ft
26 lb ft
89 lb in
33 lb ft
15 lb ft
18 lb ft
18 lb ft
48 lb ft
74 lb ft
18 lb ft
89 lb in
10 lb ft
11 lb ft

53 N.m

39 lb ft
25 degrees

Final Pass
Flywheel Bolt - Manual Transmission




15 lb ft
77 degrees

Final Pass
Crankshaft Position Reluctor Ring
Crankshaft Position Sensor Bolt
Cylinder Head Bolt




74 lb ft

53 N.m

First Pass

39 lb ft
25 degrees

Final Pass
Front Cover to Block Bolt
Fuel Pipe Bracket Bolt
Fuel Pressure Dampener Bolt
Fuel Pressure Sensor
Fuel Pump Bolt - High Pressure
Fuel Pump - High Pressure Line
Fuel Pump - Low Pressure Line
Fuel Pump Cover


25 N.m
10 N.m
10 N.m
33 N.m
15 N.m
30 N.m
30 N.m
10 N.m

18 lb ft
89 lb in
89 lb in
24 lb ft
11 lb ft
22 lb ft
22 lb ft
89 lb in

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 2

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fuel Rail Bolts
Generator to Block Bolt
Ignition Coil Bolt
Intake Manifold Brace Bolt
Intake Manifold to Cylinder Head Bolt
Intake Manifold to Cylinder Head Nut
Intake Manifold to Cylinder Head Stud
Knock Sensor Bolt
Lower Crankcase to Block Perimeter Bolt
Oil Cooler Bolts
Oil Filter Adapter Cover
Oil Gallery Gerotor Cover - Rear Bolt
Oil Gallery Plug - Cylinder Head
Oil Gallery Plug - Rear - Block
Oil Level Indicator Tube Bolt
Oil Pan Baffle Bolt
Oil Pan Bolts
Oil Pan Drain Plug
Oil Pressure Switch
Oil Pump Gerotor Cover Bolt
Oil Pump Pressure Relief Valve Plug
Oxygen Sensor
Piston Oil Squirter
Power Steering Pump Bolt
Power Steering Tensioner Bolt
Spark Plug
Starter Motor to Block Bolt
Thermostat Housing to Block Bolts
Throttle Body Bolt
Throttle Body Nut
Timing Chain Adjustable Guide Bolt
Timing Chain Fixed Guide Bolt
Timing Chain Oil Nozzle Bolt
Timing Chain Tensioner Bolt
Timing Chain Upper Guide Bolt
Turbocharger Air Bypass Valve Cover Bolt
Turbocharger Air Cooler Outlet Pipe Bolts
Turbocharger Brace Bracket Bolt
Turbocharger Brace Bracket Bolt
Turbocharger Brace Bracket Stud
Turbocharger Brace Nut

22 N.m
22 N.m
10 N.m
22 N.m
22 N.m
22 N.m
15 N.m
25 N.m
25 N.m
22 N.m
22 N.m
6 N.m
35 N.m
60 N.m
10 N.m
14 N.m
25 N.m
25 N.m
26 N.m
6 N.m
40 N.m
42 N.m
15 N.m
25 N.m
22 N.m
20 N.m
53 N.m
10 N.m
10 N.m
10 N.m
10 N.m
12 N.m
10 N.m
10 N.m
10 N.m
7 N.m
25 N.m
22 N.m
50 N.m
25 N.m
50 N.m

16 lb ft
16 lb ft
89 lb in
16 lb ft
16 lb ft
16 lb ft
11 lb ft
18 lb ft
18 lb ft
16 lb ft
16 lb ft
53 lb in
26 lb ft
44 lb ft
89 lb in
10 lb ft
18 lb ft
18 lb ft
19 lb ft
53 lb in
30 lb ft
31 lb ft
11 lb ft
18 lb ft
16 lb ft
15 lb ft
39 lb ft
89 lb in
89 lb in
89 lb in
89 lb in
106 lb in
89 lb in
89 lb in
89 lb in
62 lb in
18 lb ft
16 lb ft
37 lb ft
18 lb ft
37 lb ft

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 3

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Turbocharger Coolant Feed Pipe Bolt
Turbocharger Coolant Feed Pipe Mounting Bolt
Turbocharger Coolant Return Pipe Bolt
Turbocharger Exhaust Pipe Heat Shield Bolt
Turbocharger Exhaust Pipe Nut
Turbocharger Exhaust Pipe Stud
Turbocharger Heat Shield Bolt
Turbocharger Nut
Turbocharger Oil Feed Pipe Bolt
Turbocharger Oil Return Pipe Bolt
Turbocharger Wastegate Regulator Solenoid Valve Bracket
Bolt
Vent Tube to Cylinder Head
Water Jacket Drain Plug
Water Pipe Support Bracket Bolt
Water Pump Access Cover Bolt
Water Pump/Balance Shaft Chain Tensioner Bolt
Water Pump Bolts
Water Pump Drain Plug
Water Pump Sprocket Bolt

58 N.m
20 N.m
10 N.m
20 N.m
10 N.m
50 N.m
50 N.m
10 N.m
30 N.m
20 N.m
10 N.m

43 lb ft
15 lb ft
89 lb in
15 lb ft
89 lb in
37 lb ft
37 lb ft
89 lb in
22 lb ft
15 lb ft
89 lb in

7 N.m

62 lb in

15 N.m
20 N.m
10 N.m
10 N.m
10 N.m
25 N.m
20 N.m
10 N.m

11 lb ft
15 lb ft
89 lb in
89 lb in
89 lb in
18 lb ft
15 lb ft
89 lb in

ENGINE MECHANICAL SPECIFICATIONS
Engine Mechanical Specifications
Specification
Application

Metric

English

General Data
Inline 4 Cylinder



Engine Type



Displacement



RPO

LNF



Liter (VIN)

A, M



Bore



Stroke

2.0 L

122 CID

85.992-86.008 mm

3.3880-3.3887 in

86 mm

3.388 in
9.2:1

Compression Ratio
Balance Shaft


0.030-0.060 mm

0.0012-0.0024 in

Bearing Diameter - Inside - Carrier

20.050-20.063 mm

0.7894-0.7899 in

Bearing Diameter - Outside - Carrier

41.975-41.995 mm

1.6526-1.6534 in



Bearing Clearance




Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 4

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

20.000-20.020 mm

0.7874-0.7882 in

0.033-0.102 mm

0.0013-0.0040 in

Bushing Diameter - Inside

36.775-36.835 mm

1.4489-1.4512 in



Bushing Journal Diameter

36.723-36.743 mm

1.4458-1.4466 in



End Play

0.050-0.300 mm

0.0020-0.0118 in



Bearing Journal Diameter



Bushing Clearance



Block


Balance Shaft Bearing Bore Diameter - Carrier

42.000-42.016 mm

1.6535-1.6542 in



Balance Shaft Bushing Bore Diameter

40.763-40.776 mm

1.6048-1.6054 in



Crankshaft Main Bearing Bore Diameter

64.068-64.082 mm

2.5224-2.5229 in



Cylinder Bore Diameter

85.992-86.008 mm

3.3880-3.3887 in



Cylinder Bore Out-of-Round - Maximum

0.010 mm

0.0004 in



Cylinder Bore Taper - Maximum

0.010 mm

0.0004 in



Cylinder Head Deck Surface Flatness - Longitude

0.050 mm

0.002 in



Cylinder Head Deck Surface Flatness - Overall

0.10 mm

0.0039 in

0.030 mm

0.0012 in

0.040-0.307 mm

0.0016-0.0121 in

Cylinder Head Deck Surface Flatness - Transverse
Camshaft




Camshaft End Play



Camshaft Journal Diameter

26.935-26.960 mm

1.0604-1.0614 in



Camshaft Journal Diameter - Front

34.960-34.935 mm

1.3774-1.3764 in

30.020-30.175 mm

1.1828-1.1889 in

0.029-0.073 mm

0.0011-0.0029 in

Camshaft Thrust Surface - with Camshaft Actuator
Installed
Connecting Rod




Connecting Rod Bearing Clearance



Connecting Rod Bore Diameter - Bearing End

52.118-52.134 mm

2.0519-2.05252 in



Connecting Rod Bore Diameter - Pin End

23.007-23.017 mm

0.9058-0.9062 in



Connecting Rod Side Clearance

0.070-0.370 mm

0.0028-0.0146 in



Connecting Rod Straightness - Bend - Maximum

0.021 mm

0.0083 in

Connecting Rod Straightness - Twist - Maximum
Crankshaft

0.04 mm

0.0157 in

49.000-49.014 mm

1.9291-1.9297 in





Connecting Rod Journal Diameter



Crankshaft End Play

0.050-0.380 mm

0.0012-0.0150 in



Crankshaft Main Bearing Clearance

0.031-0.067 mm

0.0012-0.0026 in

55.994-56.008 mm

2.2045-2.2050 in

Crankshaft Main Journal Diameter
Cylinder Head


Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 5

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5



Deck Straightness - in 150 mm (5.91 in)

0.05 mm

0.0019 in



Deck Straightness - in 25 mm (0.985 in)

0.025 mm

0.0009 in



Between Head Bolt Holes

0.030 mm

0.0011 in



Surface Flatness - Block Deck - Longitude

0.050 mm

0.002 in



Surface Flatness - Block Deck - Overall

0.1 mm

0.004 in



Surface Flatness - Block Deck - Transverse

0.030 mm

0.0012 in



Valve Guide Bore - Exhaust

6.000-6.012 mm

0.2362-0.2367 in



Valve Guide Bore - Intake

6.000-6.012 mm

0.2362-0.2367 in

Valve Lifter Bore Diameter - Stationary Lash
Adjusters
Lubrication System

12.013-12.037 mm

0.4730-0.4739 in

Oil Pressure - Minimum - @1000 RPM

344.75-551.60 kPa

50-80 psi

4.8L

5.0 quarts





Oil Capacity
Piston Rings




Piston Ring End Gap - First Compression Ring

0.20-0.35 mm

0.0078-0.0138 in



Piston Ring End Gap - Second Compression Ring

0.35-0.55 mm

0.014-0.022 in



Piston Ring End Gap - Oil Control Ring - Rails

0.25-0.75 mm

0.010-0.030 in



Piston Ring to Groove Clearance - First Compression
Ring

0.040-0.080 mm

0.0016-0.0031 in



Piston Ring to Groove Clearance - Second
Compression Ring

0.003-0.068 mm

0.0001-0.0027 in



Piston Ring to Groove Clearance - Oil Control Ring

0.024-0.176 mm

0.0009-0.0069 in



Piston Ring Thickness - First Compression Ring

1.170-1.190 mm

0.0461-0.0469 in



Piston Ring Thickness - Second Compression Ring

1.471-1.490 mm

0.0579-0.0587 in



Piston Ring Thickness - Oil Control Ring - Rail Maximum

0.473 mm

0.0186 in

0.96-1.04 mm

0.0378-0.0409 in

Piston Ring Thickness - Oil Control Ring - Spacer
Pistons and Pins




Pin - Piston Pin Clearance to Connecting Rod Bore

0.009-0.023 mm

0.0004-0.0009 in



Pin - Piston Pin Clearance to Piston Pin Bore

0.005-0.015 mm

0.0002-0.0006 in



Pin - Piston Pin Diameter

22.995-23.000 mm

0.9053-0.9055 in



Pin - Piston Pin End Play

0.320-1.278 mm

0.0126-0.0503 in



Piston - Piston Diameter - @14.5 mm up

85.967-85.982 mm

3.3845-3.3851 in



Piston - Piston Pin Bore Diameter

23.005-23.010 mm

0.9057-0.9059 in

2.001-2.003 mm

0.0788-0.0789 in

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 6

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5



Piston - Piston Ring Groove Width - Oil Control



Piston - Piston Ring Groove Width - Second

1.52-1.54 mm

0.0598-0.0606 in



Piston - Piston Ring Groove Width - Top

1.23-1.25 mm

0.0484-0.0492 in

0.010-0.041 mm

0.0004-0.0016 in

Piston - Piston To Bore Clearance
Valve System




Valves - Valve Face Runout - Maximum

0.04 mm

0.0016 in



Valves - Valve Seat Runout - Maximum

0.05 mm

0.0020 in



Valves - Valve Stem Diameter - Exhaust

5.935-5.950 mm

0.2337-0.2343 in



Valves - Valve Stem Diameter - Intake

5.955-5.970 mm

0.2344-0.2355 in



Valves - Valve Stem to Guide Clearance - Exhaust

0.050-0.077 mm

0.0020-0.0026 in



Valves - Valve Stem to Guide Clearance - Intake

0.030-0.057 mm

0.0012-0.0022 in



Valve Lifters - Valve Lifter Diameter - Stationary
Lash Adjuster

11.986-12.000 mm

0.0005-0.0020 in



Valve Lifters - Valve Lifter-to-Bore Clearance Stationary Lash Adjuster

0.013-0.051 mm

3.2210-3.2299 in



Valve Springs - Valve Spring Load - Open - @22.5
mm

525.0-575.0 N. - Eng Spec.



Valve Springs - Valve Spring Load - Closed - @32.5
mm

245.0-271.0 N. - Eng Spec.

ADHESIVES, FLUIDS, LUBRICANTS, AND SEALERS

Application
# 6 Intake Rear Camshaft Cap
Balance Shaft Bearings
Cam Lobes
Crank Sensor O-ring
Cylinder Bores
Cylinder Head Plugs
Engine Block Threaded Plugs
Engine Block to Bedplate
Engine Oil
Engine Oil Level Indicator Tube O-ring
Fuel Injector O-rings
Fuel Injector Tip Insulators
Intake and Exhaust Valve Stems
Main Bearings

Type of Material
Sealant
Engine Oil
Engine Oil
Engine Oil
Engine Oil
Sealant
Sealant
Sealant
Engine Oil
Lubricant
Engine Oil
Engine Oil
Lubricant
Lubricant

GM Part Number
United States
Canada
12378521
88901148
12346184
10953495
12346184
10953495
12346184
10953495
12346184
10953495
12345382
10953489
12346004
10953480
12378521
88901148
12346184
10953495
12345501
992704
12346184
10953495
12346184
10953495
12345501
992704
12345501
992704

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 7

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Oil Filter Cap - Threads and O-ring Lead-in
Chamfers
Oil Pan to Bedplate Joint
Oil Pump - Pump Elements
Oxygen Sensor Threads
Piston Pin to Piston/Rod - Pin Bores of Piston
and Rod
Rod Bearings - Rod Pins of Crankshaft
Stationary Hydraulic Lash Adjusters
Timing Chain Guide Bolt Access Hole Plug
Valve Rocker Arm/Valve Tip
Water Feed Tube O-rings
Water Pump Drain Plug

Engine Oil

12346184

10953495

Sealant
Engine Oil
Anti-seize

12378521
12346184
12397953

88901148
10953495
-

Engine Oil

12346184

10953495

Engine Oil
Lubricant
Sealant
Lubricant
Lubricant
Sealant

12346184
12345501
12345382
12345501
12345579
12346004

10953495
992704
10953489
992704
1974984
10953480

THREAD REPAIR SPECIFICATIONS
Engine Block - Front View

Fig. 1: Identifying Bolt Size & Locations On Engine Block - Front View
Courtesy of GENERAL MOTORS CORP.
Engine Block - Front View
Service
Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 8

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Call
Out
1
2
3
4

Thread
Size

Counterbore
Insert Drill
Tap
Tool
J 42385-850
M8 x 1.25
210
206
207
208
M12 x 1.75 855
856
857
858
M10 x 1.5
215
211
212
213
M6 x 1
205
201
202
203

Driver
209
859
214
204

Drill Depth
Maximum
MM
IN
23.5
0.93
33.5
1.32
24.5
0.96
20
0.787

Tap Depth
Maximum
MM
IN
18.5
0.73
26.5
1.04
19.5
0.77
16
0.63

Engine Block - Back View

Fig. 2: Identifying Bolt Size & Locations On Engine Block - Back View
Courtesy of GENERAL MOTORS CORP.
Engine Block - Back View
Service
Call
Thread
Counterbore
Out
Insert Drill
Tap
Size
Tool
J 42385-850
1
M8 x 1.25
210
206
207
208
2
M10 x 1.5
215
211
212
213
3
M12 x 1.75 855
856
857
858
4
M16 x 1.5
860
861
862
863

Driver
209
214
859
864

Drill Depth
Maximum
MM
IN
24
0.945
29
1.161
39
1.535
21
0.827

Tap Depth
Maximum
MM
IN
THRU
THRU
33.5 1.32
15 0.59

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 9

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Engine Block - Right Side View

Fig. 3: Identifying Bolt Size & Locations On Engine Block - Right Side View
Courtesy of GENERAL MOTORS CORP.
Engine Block - Right Side View
Service
Thread
Counterbore
Call
Size
Insert Drill
Tool
Tap
Out
J 42385-850
1
M6 x 1
205
201
202
203
2
M10 x 1.5
215
211
212
213
3
M12 x 1.75 865
856
857
858

Driver
204
214
859

Drill Depth
Maximum
MM
IN
22.5
0.886
34
1.339
19.5
0.768

Tap Depth
Maximum
MM
IN
16
0.63
27
1.063
12.5
0.49

Engine Block - Bottom View

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 10

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 4: Identifying Bolt Size & Locations On Engine Block - Bottom
Courtesy of GENERAL MOTORS CORP.
Engine Block - Bottom View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M8 x 1.25
210
206
207
208
2
M10 x 1.5
514
511
N/A
512

Driver
209
513

Drill Depth
Maximum
MM
IN
28
1.102
60
2.362

Tap Depth
Maximum
MM
IN
22
0.87
53.5
2.11

Engine Block - Left Side View

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 11

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 5: Identifying Bolt Size & Locations On Engine Block - Left Side View
Courtesy of GENERAL MOTORS CORP.
Engine Block - Left Side View
Service
Call
Thread
Counterbore
Out
Size
Tool
Insert Drill
Tap
J 42385-850
1
M6 x 1
205
201
202
203
2
M10 x 1.5
215
211
212
213
3
M8 x 1.25
210
206
207
208
4
M12 x 1.75 865
856
857
858
5
M12 x 1.75 865
856
857
858

Driver
204
214
209
859
859

Drill Depth
Maximum
MM
IN
20.5
0.807
23.5
0.925
30.5
1.201
15.5
0.61
19.5
0.778

Tap Depth
Maximum
MM
IN
16.5
0.65
18
0.71
22.5
0.89
12.5
0.49
12.5
0.49

Engine Block - Top View

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 12

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 6: Identifying Bolt Size & Locations On Engine Block - Top
Courtesy of GENERAL MOTORS CORP.
Engine Block - Top View
Service
Thread
Counterbore
Call
Size
Insert Drill
Tool
Tap
Out
J 42385-850
1
M8 x 1.25
210
206
207
208
2
M11 x 1.5
507
504
N/A
505
3
M12 x 1.75 865
856
857
858

Driver
209
506
859

Drill Depth
Maximum
MM
IN
23.5
0.925
77.5
3.053
13.5
0.531

Tap Depth
Maximum
MM
IN
18.5
0.73
70
2.758
12.5
0.49

Lower Crankcase - Front View

Microsoft
Tuesday, May 18, 2010 1:01:00 PM

Page 13

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 7: Identifying Bolt Size & Locations On Lower Crankcase - Front View
Courtesy of GENERAL MOTORS CORP.
Lower Crankcase - Front View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M8 x 1.25
210
206
207
208
2
M8 x 1.25
210
206
207
208

Driver
209
209

Drill Depth
Maximum
MM
IN
23.5
0.925
30.5
1.201

Tap Depth
Maximum
MM
IN
18.5
0.73
25.5
1.00

Lower Crankcase - Back View

Fig. 8: Identifying Bolt Size & Locations On Lower Crankcase - Back
Courtesy of GENERAL MOTORS CORP.
Lower Crankcase - Back View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M10 x 1.5
215
211
212
213

Driver
214

Drill Depth
Maximum
MM
IN
29.5
1.161

Tap Depth
Maximum
MM
IN
THRU

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 14

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Lower Crankcase - Bottom View

Fig. 9: Identifying Bolt Size & Locations On Lower Crankcase - Bottom
Courtesy of GENERAL MOTORS CORP.
Lower Crankcase - Bottom View
Service
Call
Thread
Counterbore
Out
Insert Drill
Tap
Size
Tool
J 42385-850
1
M8 x 1.25
210
206
207
208

Driver
209

Drill Depth
Maximum
MM
IN
23.5
0.925

Tap Depth
Maximum
MM
IN
18.5
0.73

Lower Crankcase - Right View

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 15

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 10: Identifying Bolt Size & Locations On Lower Crankcase - Right
Courtesy of GENERAL MOTORS CORP.
Lower Crankcase - Right View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M10 x 1.5
215
211
212
213

Driver
214

Drill Depth
Maximum
MM
IN
34
1.339

Tap Depth
Maximum
MM
IN
27
1.063

Lower Crankcase - Left View

Fig. 11: Identifying Bolt Size & Locations On Lower Crankcase - Left
Courtesy of GENERAL MOTORS CORP.
Lower Crankcase - Left View
Service
Thread
Counterbore
Call
Size
Insert Drill
Tool
Tap
Out
J 42385-850
1
M8 x 1.25
210
211
212
213

Driver
214

Drill Depth
Maximum
MM
IN
34
1.339

Tap Depth
Maximum
MM
IN
27
1.063

Cylinder Head - Top View
Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 16

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 12: Identifying Bolt Size & Locations On Cylinder Head - Top
Courtesy of GENERAL MOTORS CORP.
Cylinder Head - Top View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M6 x 1
205
852
N/A
203
2
M6 x 1
205
201
202
203
3
M14 x 1.75 856
857
N/A
858
4
M8 x 1.25
854
853
N/A
208

Driver
204
204
859
209

Drill Depth
Maximum
MM
IN
23
0.906
20
0.787
THRU
30
1.182

Tap Depth
Maximum
MM
IN
19
0.748
16
0.63
THRU
27
1.063

Cylinder Head - Intake Manifold Deck View

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 17

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 13: Identifying Bolt Size & Locations On Cylinder Head - Intake Manifold Deck
Courtesy of GENERAL MOTORS CORP.
Cylinder Head - Intake Manifold Deck View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M6 x 1
205
201
202
203
2
M8 x 1.25
210
206
207
208
3
M8 x 1.25
205
201
202
203

Driver
204
209
204

Drill Depth
Maximum
MM
IN
20
0.787
20
0.787
16
0.630

Tap Depth
Maximum
MM
IN
16
0.63
16
0.63
12
0.473

Cylinder Head - Exhaust Manifold Deck View

Fig. 14: Identifying Bolt Size & Locations On Cylinder Head - Exhaust Manifold Deck
Courtesy of GENERAL MOTORS CORP.
Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 18

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Cylinder Head - Exhaust Manifold Deck View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M6 x 1
205
201
202
203
2
M8 x 1.25
210
206
207
208

Driver
204
209

Drill Depth
Maximum
MM
IN
20
0.78
25
0.984

Tap Depth
Maximum
MM
IN
16
0.63
20
0.78

Drill Depth
Maximum
MM
IN
20
0.787
25
0.984

Tap Depth
Maximum
MM
IN
16
0.63
20
0.787

Cylinder Head - Front View

Fig. 15: Identifying Bolt Size & Locations On Cylinder Head - Front
Courtesy of GENERAL MOTORS CORP.
Cylinder Head - Front View
Service
Call
Thread
Counterbore
Out
Size
Insert Drill
Tool
Tap
J 42385-850
1
M6 x 1
205
201
202
203
2
M8 x 1.25
210
206
207
208

Driver
204
209

Cylinder Head - Back View

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 19

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 16: Identifying Bolt Size & Locations On Cylinder Head - Back
Courtesy of GENERAL MOTORS CORP.
Cylinder Head - Back View
Service
Call
Thread
Counterbore
Out
Size
Tool
Insert Drill
Tap
J 42385-850
1
M8 x 1.25
210
206
207
208
2
M12 x 1.75 865
856
857
858
3
M6 x 1
205
201
202
203

Driver
209
859
204

Drill Depth
Maximum
MM
IN
25
0.984
18
0.709
20
0.787

Tap Depth
Maximum
MM
IN
20
0.787
14
0.551
16
0.63

COMPONENT LOCATOR
DISASSEMBLED VIEWS

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 20

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 17: Cylinder Head and Components
Courtesy of GENERAL MOTORS CORP.
Callout
1
2

Component Name
Camshaft Position Actuator Solenoid Valve - Intake
Camshaft Position Actuator Solenoid Valve Bolt

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 21

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43

Camshaft Position Actuator Solenoid Valve Bolt
Camshaft Position Actuator Solenoid Valve - Exhaust
Upper Intake Manifold Sight Shield Grommet
Ball Stud
Upper Intake Manifold Sight Shield Grommet
Turbocharger Coolant Feed Pipe Fitting
Turbocharger Coolant Feed Hose Gasket
Turbocharger Coolant Feed Hose Clamp
Turbocharger Coolant Feed Hose
Turbocharger Coolant Feed Hose Bolt
Turbocharger Coolant Feed Hose Gasket
Turbocharger Coolant Feed Hose Clamp
Upper Intake Manifold Sight Shield Grommet
Ball Stud
Ignition Coil Bolt
Ignition Coil Bolt Retainer
Ignition Coil
Spark Plug
Camshaft Cover Bolt
Camshaft Cover Bolt Retainer
Oil Fill Cap
Oil Fill Cap Seal
Camshaft Cover
Camshaft Cover Seal
Camshaft Cover Seal
Camshaft Cap Bolt
Camshaft Cap
Camshaft Cap
Camshaft Cap
Exhaust Camshaft
Intake Camshaft
Camshaft Position Sensor Bolt
Camshaft Position Sensor
Camshaft Position Sensor O-Ring
Roller Finger Follower
Hydraulic Lash Adjuster
Roller Finger Follower
Hydraulic Lash Adjuster
Cylinder Head Bolt
Coolant Air Bleed Fitting
Valve Keys

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 22

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68

Valve Spring Retainer
Valve Spring
Valve Stem Seal
Small Cylinder Head Bolt
Cylinder Head
Timing Chain Guide Bolt Access Hole
Exhaust Valve
Intake Valve
Camshaft Position Sensor Bolt
Camshaft Position Sensor - Intake
Camshaft Position Sensor O-Ring
Cylinder Head Gallery Plug
Rear Lift Bracket
Rear Lift Bracket Bolt
Cylinder Head Cover Plate Seal
Cylinder Head Cover Plate
Cylinder Head Cover Plate Bolt
Fuel Injector Seal
Fuel Injector
Fuel Injector O-Ring
Fuel Injector Hold Down Clamp
Fuel Rail
Fuel Rail Pressure Sensor
Fuel Injector Wiring Harness
Fuel Rail Bolt

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 23

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 18: Intake Manifold and Components
Courtesy of GENERAL MOTORS CORP.
Callout
1
2
3
4
5
6
7
8
9
10
11
12

Component Name
Evaporative (EVAP) Emission Purge Solenoid Valve Bolt
EVAP Purge Solenoid Valve
Manifold Absolute Pressure (MAP) Sensor Bolt
MAP Sensor
Fuel Pump Lifter
High Pressure Fuel Pump Gasket
High Pressure Fuel Pump O-Ring
High Pressure Fuel Pump
High Pressure Fuel Pump Bolt
Fuel Feed Line
Fuel Feed Line Bolt
High Pressure Fuel Pump Insulator

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 24

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32

High Pressure Fuel Pump Cover
High Pressure Fuel Line
Fuel Injector Insulator
Oil Indicator Tube
Oil Indicator
Intake Manifold Brace
Intake Manifold Brace Stud
Oil Indicator O-Ring
Charger AIR Bypass Tube Clamp
Charger AIR Bypass Tube Assembly
Charger AIR Bypass Valve Tank Assembly Nut
Charger AIR Bypass Valve Tank Assembly, Some Models
Charger AIR Bypass Valve Solenoid Bolt
Charger AIR Bypass Valve Solenoid
Throttle Body Bolt
Throttle Body
Throttle Body Seal
Power Brake Booster Fitting
Intake Manifold
Intake Manifold Gasket

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 25

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 19: Exhaust Manifold and Components
Courtesy of GENERAL MOTORS CORP.
Callout
1
2
3
4
5
6
7
8
9
10
11

Component Name
Turbocharger Wastegate Regulator Solenoid Hose
Turbocharger Wastegate Regulator Solenoid Hose Clamp
Turbocharger Wastegate Regulator Solenoid Hose
Turbocharger Wastegate Regulator Solenoid Valve Assembly
Turbocharger Wastegate Regulator Solenoid Valve Bracket
Turbocharger Wastegate Regulator Solenoid Valve Bracket Bolt/Screw
Turbocharger Wastegate Regulator Solenoid Hose
Turbocharger Wastegate Regulator Solenoid Hose Clamp
Turbocharger Oil Feed Pipe
Turbocharger Oil Feed Pipe Bolt
Turbocharger Oil Feed Pipe Gasket

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 26

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52

Turbocharger Oil Feed Pipe Gasket
Turbocharger Oil Feed Pipe Bolt
Turbocharger Coolant Return Pipe Gasket
Turbocharger Coolant Return Pipe Bolt
Turbocharger Coolant Return Pipe
Turbocharger Coolant Return Pipe Bolt
Turbocharger Coolant Return Pipe Gasket
Turbocharger Coolant Feed Pipe
Turbocharger Coolant Feed Pipe Gasket
Turbocharger Coolant Feed Pipe Bolt
Engine Coolant Heater
Engine Coolant Heater Bolt
Exhaust Manifold Heat Shield Bolt
Exhaust Manifold Heat Shield Bolt
Exhaust Manifold Heat Shield
Exhaust Manifold Nut
Exhaust Manifold
Exhaust Manifold Gasket
Exhaust Manifold Stud
Oxygen Sensor Fastener
Oxygen Sensor
Oxygen Sensor Gasket
Turbocharger Exhaust Pipe Heat Shield Bolt
Turbocharger Exhaust Pipe Heat Shield
Turbocharger Exhaust Pipe Nut
Turbocharger Exhaust Pipe
Turbocharger Exhaust Pipe Seal
Turbocharger Exhaust Pipe Bolt
Turbocharger Exhaust Pipe Stud
Turbocharger Brace Nut
Turbocharger Brace Bracket
Turbocharger Brace Stud
Turbocharger Brace
Turbocharger Brace Bracket Bolt
Turbocharger Brace Bracket
Turbocharger Brace Bracket Stud
Turbocharger Brace Nut
Turbocharger Brace Bracket Bolt
Turbocharger Brace Bracket Bolt
Turbocharger Gasket
Turbocharger

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 27

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

54
55
56
57
58
59
60
61
62
63
64
65
66

Turbocharger Air Bypass Valve Spring
Turbocharger Air Bypass Diaphragm Assembly
Turbocharger Oil Return Pipe O-Ring
Turbocharger Oil Return Pipe
Turbocharger Oil Return Pipe Bolt
Turbocharger Oil Return Pipe Gasket
Turbocharger Air Bypass Valve Cover Bolt
Turbocharger Air Bypass Valve Cover
Turbocharger Exhaust Pipe Stud
Turbocharger Air Cooler Outlet Pipe Seal
Turbocharger Air Cooler Outlet Pipe
Turbocharger Air Cooler Outlet Pipe Bolt
Turbocharger Heat Shield
Turbocharger Heat Shield Bolts

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 28

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 20: Engine Block and Components
Courtesy of GENERAL MOTORS CORP.
Callout
1
2
3
4
5
6
7

Component Name
Water Pump to Engine Block Seal
Water Pump Seal
Water Pump
Water Pump Bolt
Outlet Pipe O-rings
Outlet Pipe
Coolant Thermostat Housing Bolt

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 29

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48

Coolant Thermostat Housing
Thermostat Housing to Block Gasket
Coolant Thermostat Housing Seal
Coolant Temperature Sensor
Thermostat
Coolant Inlet
Coolant Inlet Bolt
Water Pipe Support Bracket
Water Pipe Support Bracket Bolt
Water Pipe Support Bracket Bolt Stud
Piston Ring Assembly
Piston Assembly
Connecting Rod Bushing
Connecting Rod
Connecting Rod Bearing
Connecting Rod Cap Bolt
Oil Cooler O-ring
Oil Cooler
Oil Cooler Bolt
Front Lift Bracket
Front Lift Bracket Bolt
Cylinder Head Gasket
Cylinder Bore Liner
Cylinder Head Alignment Pin
Oil Filter Cap
Oil Filter Cap O-ring
Oil Filter
Engine Block Gallery Plug
Engine Block to Transaxle Alignment Pin
Crankshaft Position Sensor
Crankshaft Position Sensor Bolt
Oil Pressure Switch
Piston Oil Nozzle Assembly
Manual Transaxle Flywheel to Crankshaft Bolt
Flywheel - Manual Transaxle
Automatic Transaxle Flywheel to Crankshaft Bolt
Flywheel - Automatic Transaxle
Crankshaft Rear Seal
Engine Block
Crankshaft Thrust Bearing - Upper
Crankshaft Bearing - Upper

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 30

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

50
51
52
53
54
55
56
57
58
59
60
61
62
63

Crankshaft
Crankshaft Thrust Bearing - Lower
Crankshaft Bearing - Lower
Lower Crankcase Main Bearing Bolt
Lower Crankcase Perimeter Bolt
Engine Oil Pan
Engine Oil Pan Alignment Pins
Lower Crankcase Main Bearing Bolt
Engine Oil Pan Drain Plug
Engine Oil Pan Bolt
Engine Oil Pan Long Bolt
Knock Sensor - Rear
Knock Sensor - Front
Starter Bolt
Starter

Fig. 21: Timing Chain and Components
Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 31

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Courtesy of GENERAL MOTORS CORP.
Callout
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38

Component Name
Timing Chain Tensioner Body
Timing Chain Tensioner Seal
Adjustable Timing Chain Guide
Adjustable Timing Chain Guide Bolt
Timing Chain
Fixed Timing Chain Guide Bolt
Fixed Timing Chain Guide
Timing Chain Drive Sprocket
Friction Washers
Timing Chain Oil Nozzle Bolt
Timing Chain Oil Nozzle
Camshaft Position Actuator Bolt
Intake Camshaft Position Actuator
Camshaft Position Actuator Bolt
Exhaust Camshaft Position Actuator
Upper Timing Chain Guide
Upper Timing Chain Guide Bolt
Balance Shaft Drive Sprocket Bolts
Exhaust Balance Shaft Drive Sprocket
Intake Balance Shaft Drive Sprocket
Exhaust Balance Shaft Bearing Carrier
Intake Balance Shaft Bearing Carrier
Exhaust Balance Shaft
Intake Balance Shaft
Balance Shaft Rear Bearing
Water Pump Drive Sprocket Bolt
Water Pump Drive Sprocket
Balance Shaft Drive Chain Tensioner Assembly Bolt
Balance Shaft Drive Chain Tensioner Assembly
Adjustable Balance Shaft Drive Chain Guide Bolt
Adjustable Balance Shaft Drive Chain Guide
Balance Shaft Drive Chain
Balance Shaft Drive Chain Guide Bolt
Balance Shaft Drive Chain Guide
Balance Shaft Drive Sprocket
Balance Shaft Drive Chain Guide
Balance Shaft Drive Chain Guide Bolt
Engine Front Cover Alignment Pins

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 32

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56

Engine Front Cover Gasket
Oil Pump Cover Bolt
Oil Pump Cover
Oil Pump Gear
Oil Pump Inner Rotor
Engine Front Cover
Engine Front Cover Bolt
Crankshaft Front Oil Seal
Crankshaft Balancer
Crankshaft Balancer Bolt
Engine Front Cover Bolt
Oil Pressure Relief Valve
Oil Pressure Relief Valve O-Ring
Water Pump Sprocket Access Cover Bolt
Water Pump Sprocket Access Cover
Water Pump Sprocket Access Cover Gasket
Belt Tensioner Bolt
Belt Tensioner

ENGINE IDENTIFICATION

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 33

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 22: Locating Engine Identification Numbers
Courtesy of GENERAL MOTORS CORP.
Identification can be made through the use of the broadcast code label (1) on the engine front cover and the use
of the partial vehicle identification number (VIN) etched on the oil filter bowl (2).

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 34

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Fig. 23: View Of Broadcast Code Label
Courtesy of GENERAL MOTORS CORP.
Callout
1
2
3
4
5
6
7
8
9
10

Component Name
Barcode
Sequence Number
Day
Month
Year
Engine Assembly Plant
Broadcast Code
Part Designation
Engine Assembly Number
Broadcast Code

The partial VIN identifies the specific vehicle by sequence number.
Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 35

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

DIAGNOSTIC INFORMATION AND PROCEDURES
DIAGNOSTIC STARTING POINT - ENGINE MECHANICAL
Begin the system diagnosis by reviewing the Disassembled Views, Engine Component Description,
Lubrication Description, and Drive Belt System Description. Reviewing the description and operation
information helps you determine the correct symptom diagnostic procedure when a malfunction exists.
Reviewing the description and operation information also helps you determine if the condition described by the
customer is normal operation. Refer to Symptoms - Engine Mechanical in order to identify the correct
procedure for diagnosing the system and where the procedure is located.
SYMPTOMS - ENGINE MECHANICAL
Strategy Based Diagnostics

1. Perform the Diagnostic System Check - Vehicle before using the symptom tables, if applicable.
2. Review the system operations in order to familiarize yourself with the system functions. Refer to
Disassembled Views, Engine Component Description, and Lubrication Description.
All diagnosis on a vehicle should follow a logical process. Strategy based diagnostics is a uniform approach for
repairing all systems. The diagnostic flow may always be used in order to resolve a system condition. The
diagnostic flow is the place to start when repairs are necessary.
Visual/Physical Inspection








Inspect for aftermarket devices which could affect the operation of the engine.
Inspect the easily accessible or visible system components for obvious damage or conditions which could
cause the symptom.
Inspect for the correct oil level, proper oil viscosity, and correct filter application.
Verify the exact operating conditions under which the concern exists. Note factors such as engine RPM,
ambient temperature, engine temperature, amount of engine warm-up time, and other specifics.
Compare the engine sounds, if applicable, to a known good engine and ensure you are not trying to
correct a normal condition.

Intermittent

Test the vehicle under the same conditions that the customer reported in order to verify the system is operating
properly.
Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:



Base Engine Misfire without Internal Engine Noises
Base Engine Misfire with Abnormal Internal Lower Engine Noises

Microsoft
Tuesday, May 18, 2010 1:01:01 PM

Page 36

© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5



























Base Engine Misfire with Abnormal Valve Train Noise
Base Engine Misfire with Coolant Consumption
Base Engine Misfire with Excessive Oil Consumption
Engine Noise on Start-Up, but Only Lasting a Few Seconds
Upper Engine Noise, Regardless of Engine Speed
Lower Engine Noise, Regardless of Engine Speed
Engine Noise Under Load
Engine Will Not Crank - Crankshaft Will Not Rotate
Coolant in Combustion Chamber
Coolant in Engine Oil
Turbocharger Whine Noise
Turbocharger Hissing Noise
Turbocharger Oil Leak From Compressor Seal
Turbocharger Oil Leak From Turbine Seal
Turbocharger Lack of Oil Supply
Engine Compression Test
Cylinder Leakage Test
Oil Consumption Diagnosis
Oil Pressure Diagnosis and Testing
Oil Leak Diagnosis
Crankcase Ventilation System Inspection/Diagnosis
Drive Belt Chirping, Squeal, and Whine Diagnosis
Drive Belt Rumbling and Vibration Diagnosis
Drive Belt Falls Off and Excessive Wear Diagnosis
Drive Belt Tensioner Diagnosis

BASE ENGINE MISFIRE WITHOUT INTERNAL ENGINE NOISES
Cause
Correction
Abnormalities, severe cracking, bumps, or missing Replace the drive belt.
areas in the accessory drive belt
Abnormalities in the accessory drive system and/or
components may cause engine RPM variations and
lead to a misfire DTC. A misfire code may be
present without an actual misfire condition.
Worn, damaged, or mis-aligned accessory drive
Inspect the components and repair or replace, as
components or excessive pulley runout
required.
May lead to a misfire DTC.
A misfire code may be present without an actual
misfire condition.
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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

A loose or improperly installed engine flywheel or Repair or replace the flywheel and/or balancer, as
crankshaft balancer
required.
A misfire code may be present without an actual
misfire condition.
Restricted exhaust system
Repair or replace, as required.
A severe restriction in the exhaust flow can cause
significant loss of engine performance and may set a
DTC. Possible causes of restrictions include
collapsed or dented pipes or plugged mufflers and/or
catalytic converters.
Improperly installed or damaged vacuum hoses
Repair or replace, as required.
Improperly installed or leaking charge air cooler
Repair or replace, as required.
tube
Improper sealing between the intake manifold and Replace the intake manifold, gaskets, cylinder
cylinder heads or throttle body
heads, and/or throttle body, as required.
Improperly installed or damaged manifold absolute Repair or replace the MAP sensor and/or the TMAP
pressure (MAP) sensor or intake air pressure temp sensor, as required.
(TMAP) sensor
The sealing grommet of the MAP sensor should not
be torn or damaged.
Damage to the MAP sensor housing
Replace the intake manifold.
Worn or loose rocker arms
Replace the valve rocker arms, as required.
The rocker arm bearing end caps and/or needle
bearings should be intact and in the proper position.
Stuck valves
Repair or replace, as required.
Carbon buildup on the valve stem can cause the
valve not to close properly.
Excessively worn or mis-aligned timing chain
Replace the timing chain and sprockets, as required.
Worn camshaft lobes
Replace the camshaft and valve lifters.
Excessive oil pressure
1. Perform an oil pressure test. Refer to Oil
A lubrication system with excessive oil pressure
Pressure Diagnosis and Testing.
may lead to excessive valve lifter pump up and loss
2. Repair or replace the oil pump, as required.
of compression.
Faulty cylinder head gaskets and/or cracking or
other damage to the cylinder heads and engine block
cooling system passages
Coolant consumption may or may not cause the
engine to overheat.
Worn piston rings
Oil consumption may or may not cause the engine to
misfire.

1. Inspect for spark plugs saturated by coolant.
2. Inspect the cylinder heads, engine block,
and/or head gaskets.
3. Repair or replace, as required.
1. Inspect the spark plugs for oil deposits.
2. Inspect the cylinders for a loss of
compression. Refer to Engine Compression
Test.
3. Perform cylinder leak down and compression
testing to identify the cause.

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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

4. Repair or replace, as required.
Replace the sensor and/or crankshaft, as required.

A damaged crankshaft reluctor wheel
A damaged crankshaft reluctor wheel can result in
different symptoms depending on the severity and
location of the damage.






Systems with electronic communications, DIS
or coil per cylinder, and severe reluctor ring
damage may exhibit periodic loss of
crankshaft position, stop delivering a signal,
and then re-sync the crankshaft position.
Systems with electronic communication, DIS
or coil per cylinder, and slight reluctor ring
damage may exhibit no loss of crankshaft
position and no misfire may occur. However,
a DTC P0300 may be set.
Systems with mechanical communications,
high voltage switch, and severe reluctor ring
damage may cause additional pulses and
affect fuel and spark delivery to the point of
generating a DTC P0300 or P0336.

BASE ENGINE MISFIRE WITH ABNORMAL INTERNAL LOWER ENGINE NOISES
Cause
Correction
Abnormalities, severe cracking, bumps, or missing Replace the drive belt.
areas in the accessory drive belt
Abnormalities in the accessory drive system and/or
components may cause engine RPM variations,
noises similar to a faulty lower engine, and also lead
to a misfire condition. A misfire code may be
present without an actual misfire condition.
Worn, damaged, or mis-aligned accessory drive
1. Inspect the components.
components or excessive pulley runout
2. Repair or replace the components, as required.
A misfire code may be present without an actual
misfire condition.
Loose or improperly installed engine flywheel or
Repair or replace the flywheel and/or balancer, as
crankshaft balancer
required.
A misfire code may be present without an actual
misfire condition.
Worn piston rings
1. Inspect the spark plugs for oil deposits.
Oil consumption may or may not cause the engine
2. Inspect the cylinders for a loss of
to misfire.
compression. Refer to Engine Compression
Test.
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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Worn crankshaft thrust bearings
Severely worn thrust surfaces on the crankshaft
and/or thrust bearing may permit fore and aft
movement of the crankshaft, and create a DTC
without an actual misfire condition.

3. Perform cylinder leak down and compression
testing to determine the cause.
4. Repair or replace, as required.
Replace the crankshaft and bearings, as required.

BASE ENGINE MISFIRE WITH ABNORMAL VALVE TRAIN NOISE
Cause
Worn or loose rocker arms
The rocker arm bearing end caps and/or needle
bearings should intact within the rocker arm
assembly.
Stuck valves
Carbon buildup on the valve stem can cause the
valve to not close properly.
Excessively worn or mis-aligned timing chain
Worn camshaft lobes
Sticking lifters

Correction
Replace the valve rocker arms as required.

Repair or replace as required.

Replace the timing chain and sprockets as required.
Replace the camshaft and valve lash adjusters.
Replace as required.

BASE ENGINE MISFIRE WITH COOLANT CONSUMPTION
Cause
Faulty cylinder head gasket and/or cracking, or
other damage to the cylinder head and engine block
cooling system passages.
Coolant consumption may or may not cause the
engine to overheat.

Correction






Inspect for spark plugs saturated by coolant.
Perform a cylinder leak down test.
Inspect the cylinder head and engine block for
damage to the coolant passages and/or a
faulty head gasket.
Repair or replace as required.

BASE ENGINE MISFIRE WITH EXCESSIVE OIL CONSUMPTION
Cause
Worn valves, valve guides, and/or valve stem oil
seals
Worn piston rings
Oil consumption may or may not cause the engine
to misfire.

Correction
1. Inspect the spark plugs for oil deposits.
2. Repair or replace, as required.
1. Inspect the spark plugs for oil deposits.
2. Inspect the cylinders for a loss of
compression. Refer to Engine Compression
Test.

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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

3. Perform cylinder leak down and compression
testing to determine the cause.
4. Repair or replace, as required.
ENGINE NOISE ON START-UP, BUT ONLY LASTING A FEW SECONDS
Cause
Incorrect oil filter without anti-drainback feature
Incorrect oil viscosity
High valve lash adjuster leak down rate
Worn crankshaft thrust bearing
Damaged or faulty oil filter by-pass valve

Malfunctioning camshaft position actuators improper oil viscosity or contamination. The result
is camshaft actuator locking pin does not lock

Correction
Install the correct oil filter.
1. Drain the oil.
2. Install the correct viscosity oil.
Replace the lash adjusters as required.
1. Inspect the thrust bearing and crankshaft.
2. Repair or replace as required.
1. Inspect the oil filter by-pass valve for proper
operation.
2. Repair or replace as required.
1. Verify correct engine oil viscosity by
changing the engine oil and filter. Reevaluate
the concern.
2. Isolate the noise to a specific camshaft
position actuator.
3. Replace the camshaft actuator, oil and filter.

UPPER ENGINE NOISE, REGARDLESS OF ENGINE SPEED
Cause
Low oil pressure

Loose and/or worn valve rocker arm attachments
Worn valve rocker arm
Improper lubrication to the valve rocker arms

Correction
1. Perform an oil pressure test. Refer to Oil
Pressure Diagnosis and Testing.
2. Repair or replace, as required.
1. Inspect the valve rocker arm stud, nut, or bolt.
2. Repair or replace, as required.
Replace the valve rocker arm.
Inspect the following components and repair or
replace, as required:





The valve rocker arm
The valve lifter
The oil filter bypass valve
The oil pump and pump screen

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© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

The engine block oil galleries
Replace the valve spring.
Replace the valve lifters.
Replace the timing chain and sprockets.


Broken valve spring
Worn or dirty valve lifters
Stretched or broken timing chain and/or damaged
sprocket teeth
Worn, damaged, or faulty timing chain tensioners
Worn engine camshaft lobes

Worn valve guides or valve stems

Replace the timing chain tensioners.
1. Inspect the engine camshaft lobes.
2. Replace the camshaft and valve lifters, as
required.
Inspect the following components and repair, as
required:
The valves
 The valve guides
Inspect the following components and repair, as
required:


Stuck valves
Carbon on the valve stem or valve seat may cause
the valve to stay open.




The valves
The valve guides

LOWER ENGINE NOISE, REGARDLESS OF ENGINE SPEED
Cause

Correction

Low oil pressure

1. Perform an oil pressure test. Refer to Oil
Pressure Diagnosis and Testing.
2. Repair or replace damaged components, as
required.

Worn accessory drive components - abnormalities,
such as severe cracking, bumps, or missing areas in
the accessory drive belt and/or misalignment of
system components
Loose or damaged crankshaft balancer

1. Inspect the accessory drive system.
2. Repair or replace, as required.

Detonation or spark knock
Loose torque converter bolts

Loose or damaged flywheel
Damaged oil pan, contacting the oil pump screen
An oil pan that has been damaged, may improperly

1. Inspect the crankshaft balancer.
2. Repair or replace, as required.
Verify the correct operation of the ignition system.
Refer to Symptoms - Engine Controls .
1. Inspect the torque converter bolts and
flywheel.
2. Repair or replace, as required.
Repair or replace the flywheel.
1. Inspect the oil pan.
2. Inspect the oil pump screen.

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© 2006 Mitchell Repair Information Company, LLC.

2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

position the oil pump screen, preventing proper oil
flow to the oil pump.
Oil pump screen loose, damaged, or restricted

3. Repair or replace, as required.

Excessive piston-to-cylinder bore clearance

1. Inspect the piston and cylinder bore.
2. Repair, as required.

Excessive piston pin-to-bore clearance

Excessive connecting rod bearing clearance

1. Inspect the oil pump screen.
2. Repair or replace, as required.

1. Inspect the piston, piston pin, and the
connecting rod.
2. Repair or replace, as required.
Inspect the following components and repair, as
required:
The connecting rod bearings
 The connecting rods
 The crankshaft
 The crankshaft journals
Inspect the following components and repair, as
required:


Excessive crankshaft bearing clearance




Incorrect piston, piston pin, and connecting rod
installation
Pistons must be installed with the mark or dimple
on the top of the piston facing the front of the
engine. Piston pins must be centered in the
connecting rod pin bore.

The crankshaft bearings
The crankshaft journals

1. Verify the pistons, piston pins, and connecting
rods are installed correctly.
2. Repair, as required.

ENGINE NOISE UNDER LOAD
Cause
Low oil pressure

Detonation or spark knock

Correction
1. Perform an oil pressure test. Refer to Oil
Pressure Diagnosis and Testing.
2. Repair or replace, as required.
Verify the correct operation of the ignition. Refer to
Symptoms - Engine Controls .

Loose torque converter bolts

1. Inspect the torque converter bolts and
flywheel.
2. Repair, as required.

Cracked flywheel - automatic transmission

1. Inspect the flywheel bolts and flywheel.
2. Repair, as required.

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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Excessive connecting rod bearing clearance

Inspect the following components and repair, as
required:
The connecting rod bearings
 The connecting rods
 The crankshaft
Inspect the following components and repair, as
required:


Excessive crankshaft bearing clearance





The crankshaft bearings
The crankshaft journals
The cylinder block crankshaft bearing bore

ENGINE WILL NOT CRANK - CRANKSHAFT WILL NOT ROTATE
Cause
Seized accessory drive system component

Hydraulically locked cylinder




Coolant/antifreeze in cylinder
Oil in cylinder
Fuel in cylinder

Correction
1. Remove accessory drive belts.
2. Rotate crankshaft by hand at the balancer or
flywheel location.
1. Remove spark plugs and check for fluid.
2. Inspect for broken head gasket.
3. Inspect for cracked engine block or cylinder
head.
4. Inspect for a sticking fuel injector.
5. Inspect for cracked cylinder wall.

Seized automatic transmission torque converter

1. Remove the torque converter bolts.
2. Rotate crankshaft by hand at the balancer or
flywheel location.

Seized manual transmission

1. Disengage the clutch.
2. Rotate crankshaft by hand at the balancer or
flywheel location.

Broken timing chain and/or gears




Seized balance shaft




Material in cylinder




Broken valve
Piston material
Foreign material






Inspect timing chain and gears.
Repair as required.
Inspect balance shaft.
Repair as required.
Inspect cylinder for damaged components
and/or foreign materials.
Inspect for fallen cylinder wall.
Repair or replace as required.

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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Cracked cylinder wall
Seized crankshaft or connecting rod bearings







Bent or broken connecting rod




Broken crankshaft




Inspect crankshaft and connecting rod
bearings.
Inspect for fallen cylinder wall.
Repair as required.
Inspect connecting rods.
Repair as required.
Inspect crankshaft.
Repair as required.

COOLANT IN COMBUSTION CHAMBER
Cause
Correction
DEFINITION: Excessive white smoke and/or coolant type odor coming from the exhaust pipe may
indicate coolant in the combustion chamber. Low coolant levels, an inoperative cooling fan, or a faulty
thermostat may lead to an overtemperature condition which may cause engine component damage.
1. A slower than normal cranking speed may indicate coolant entering the combustion chamber. Refer
to Engine Will Not Crank - Crankshaft Will Not Rotate.
2. Remove the spark plugs and inspect for spark plugs saturated by coolant or coolant in the cylinder
bore.
3. Inspect by performing a cylinder leak down test. During this test, excessive air bubbles within the
coolant may indicate a faulty gasket or damaged component.
4. Inspect by performing a cylinder compression test. 2 cylinders side-by-side on the engine block,
with low compression, may indicate a failed cylinder head gasket. Refer to Engine Compression
Test.
Faulty cylinder head gasket
Replace the head gasket and components, as
required. Refer to Cylinder Head Cleaning and
Inspection and Cylinder Head Replacement.
Warped cylinder head
Replace the cylinder head and gasket. Refer to
Cylinder Head Cleaning and Inspection.
Cracked cylinder head
Replace the cylinder head and gasket.
Cracked cylinder liner
Replace the components, as required.
Cylinder head or block porosity
Replace the components, as required.
COOLANT IN ENGINE OIL
Cause
Correction
DEFINITION: Foamy or discolored oil or an engine oil overfill condition may indicate coolant entering
the engine crankcase. Low coolant levels, an inoperative cooling fan, or a faulty thermostat may lead to
an overtemperature condition which may cause engine component damage. Contaminated engine oil and
oil filter should be changed.
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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

1. Inspect the oil for excessive foaming or an overfill condition. Oil diluted by coolant may not
properly lubricate the crankshaft bearings and may lead to component damage. Refer to Lower
Engine Noise, Regardless of Engine Speed.
2. Inspect by performing a cylinder leak down test. During this test, excessive air bubbles within the
cooling system may indicate a faulty gasket or damaged component.
3. Inspect by performing a cylinder compression test. 2 cylinders side-by-side on the engine block
with low compression may indicate a failed cylinder head gasket. Refer to Engine Compression
Test.
Faulty cylinder head gasket

Warped cylinder head
Cracked cylinder head
Cracked cylinder liner
Cylinder head or block porosity

Replace the head gasket and components, as
required. Refer to Cylinder Head Cleaning and
Inspection and Cylinder Head Replacement.
Replace the cylinder head and gasket. Refer to
Cylinder Head Cleaning and Inspection.
Replace the cylinder head and gasket.
Replace the components, as required.
Replace the components, as required.

TURBOCHARGER WHINE NOISE
Condition
Action
Some whine noise is normal. Compare to a known good vehicle.
Worn turbocharger bearings
Visually inspect for evidence of compressor wheel
to housing contact.
Inspect for worn or damaged turbocharger bearings.
Inspect for end play causing compressor wheel to
housing contact.
TURBOCHARGER HISSING NOISE
Condition
Air inlet leaks or obstructions
Leaking or restricted exhaust system

Intake system leaks or obstructions

Action
Inspect for leaks or obstructions in the turbocharger
inlet.
1. Inspect for a leak in the exhaust system.
2. Inspect for a restricted exhaust system.
1. Inspect for leaks.
2. Inspect for obstructions.

TURBOCHARGER OIL LEAK FROM COMPRESSOR SEAL
Condition
Restricted air system

Action
Inspect for a clogged air filter element or restricted
air inlet system.

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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

Restricted exhaust system
Leaking exhaust system
Poor oil drainage from turbocharger
Restricted crankcase ventilation system
Worn internal engine components

Inspect for a restricted exhaust.
Inspect for exhaust manifold leaks.
Inspect for a restricted turbocharger oil drain pipe.
Inspect for a restricted crankcase ventilation system.
Inspect for excessive blowby or engine oil
consumption.

TURBOCHARGER OIL LEAK FROM TURBINE SEAL
Condition
Poor oil drainage from turbocharger
Restricted crankcase ventilation system
Worn internal engine components

Action
Inspect for a restricted turbocharger oil drain pipe.
Inspect for a restricted crankcase ventilation system.
Inspect for excessive blowby or engine oil
consumption.

TURBOCHARGER LACK OF OIL SUPPLY
Condition
Restricted oil supply hose

Action
Inspect for a restricted or damaged turbocharger oil
supply hose.

ENGINE COMPRESSION TEST
1.
2.
3.
4.
5.
6.
7.
8.
9.

Charge the battery if the battery is not fully charged.
Disable the ignition system.
Disable the fuel injection system.
Remove all spark plugs.
Turn the ignition to the ON position.
Depress the accelerator pedal to position the throttle plate wide open.
Start with the compression gage at zero and crank the engine through 4 compression strokes, 4 puffs.
Measure the compression for each cylinder. Record the readings.
If a cylinder has low compression, inject approximately 15 ml (1 tablespoon) of engine oil into the
combustion chamber through the spark plug hole. Measure the compression again and record the reading.
10. The minimum compression in any 1 cylinder should not be less than 70 percent of the highest cylinder.
No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure in any 1
cylinder is 1 035 kPa (150 psi), the lowest allowable pressure for any other cylinder would be 725 kPa
(105 psi). (1 035 x 70% = 725) (150 x 70% = 105).
 Normal - Compression builds up quickly and evenly to the specified compression for each cylinder.
 Piston Rings Leaking - Compression is low on the first stroke. Compression builds up with the
following strokes, but does not reach normal. Compression improves considerably when you add
oil.
 Valves Leaking - Compression is low on the first stroke. Compression usually does not build up on
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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5



the following strokes. Compression does not improve much when you add oil.
If 2 adjacent cylinders have lower than normal compression, and injecting oil into the cylinders
does not increase the compression, the cause may be a head gasket leaking between the cylinders.

CYLINDER LEAKAGE TEST
Special Tools

J 35667-A Cylinder Head Leakdown Tester or equivalent. See Special Tools.
NOTE:

A leakage test may be performed in order to measure cylinder/combustion
chamber leakage. High leakage may indicate one or more of the following
conditions:

Test











Worn or burnt valves
Broken valve springs
Stuck valve lifters
Incorrect valve lash/adjustment
Damaged piston
Worn piston rings
Worn or scored cylinder bore
Damaged cylinder head gasket
Cracked or damaged cylinder head
Cracked or damaged engine block
WARNING: Unless directed otherwise, the ignition and start switch must be in
the OFF or LOCK position, and all electrical loads must be OFF
before servicing any electrical component. Disconnect the negative
battery cable to prevent an electrical spark should a tool or
equipment come in contact with an exposed electrical terminal.
Failure to follow these precautions may result in personal injury
and/or damage to the vehicle or its components.

1. Disconnect the battery ground negative cable.
2. Remove the spark plugs. Refer to Spark Plug Replacement .
3. Rotate the crankshaft to place the piston in the cylinder being tested at top dead center (TDC) of the
compression stroke.
4. Install the J 35667-A or equivalent. See Special Tools.
NOTE:

It may be necessary to hold the crankshaft balancer bolt to prevent the
engine from rotating.

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2009 Chevrolet Cobalt LT
2009 ENGINE Engine Mechanical - 2.0L - Cobalt & G5

5. Apply shop air pressure to the J 35667-A and adjust according to the manufacturers instructions. See
Special Tools.
6. Record the cylinder leakage value. Cylinder leakage that exceeds 25 percent is considered excessive and
may require component service. In excessive leakage situations, inspect for the following conditions:
 Air leakage sounds at the throttle body or air inlet hose that may indicate a worn or burnt intake
valve or a broken valve spring.
 Air leakage sounds at the exhaust system tailpipe that may indicate a worn or burnt exhaust valve
or a broken valve spring.
 Air leakage sounds from the crankcase, oil level indicator tube, or oil fill tube that may indicate
worn piston rings, a damaged piston, a worn or scored cylinder bore, a damaged engine block or a
damaged cylinder head.
 Air bubbles in the cooling system may indicate a damaged cylinder head or a damaged cylinder
head gasket.
7. Perform the leakage test on the remaining cylinders and record the values.
OIL CONSUMPTION DIAGNOSIS
Excessive oil consumption, not due to leaks, is the use of 0.9 L (1 qt) or greater of engine oil within 3 200
kilometers (2,000 miles). The causes of excessive oil consumption include the following conditions:


External oil leaks
Tighten bolts and/or replace gaskets and oil seals as necessary.



Incorrect oil level or improper reading of oil level indicator
With the vehicle on a level surface, allow adequate drain down time and inspect for the correct oil level.



Improper oil viscosity
Use recommended SAE viscosity for the prevailing temperatures.





Continuous high speed driving and/or severe usage
Crankcase ventilation system restrictions or malfunctioning components
Valve guides and/or valve stem oil seals worn, or the seal omitted
Ream guides and install oversize service valves and/or new valve stem oil seals.



Piston rings broken, improperly installed, worn, or not seated properly
Allow adequate time for rings to seat. Replace broken or worn rings, as necessary.



Piston improperly installed or mis-fitted

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