Chevrolet Cobalt Service & Repair Manual: Component Service

Engine Control Module (ECM)

1. Retrieve percentage of remaining engine oil life using a scan tool, then record remaining engine oil life.
2. Remove ECM cover, then disconnect body wiring harness electrical connector from ECM, Fig. 1.
3. Disconnect engine wiring harness from ECM.
4. Release retaining tab and remove ECM from underhood junction block bracket.
5. Reverse procedure to install.

Camshaft Position (CMP) Sensor

Exhaust

1. Remove engine oil fill cap, then remove intake manifold cover.
2. Disconnect engine wiring harness electrical connector from CMP sensor.
3. Remove exhaust CMP sensor mounting bolt, then the sensor and O-ring, Fig. 2.
4. Reverse procedure to install, noting the following:
  a. Lubricate O-ring seal with clean engine oil.
  b. Torque mounting bolt to 89 inch lbs.

Intake

1. Remove engine oil fill cap, then remove intake manifold cover.
2. Disconnect engine wiring harness electrical connector from CMP sensor.
3. Remove intake CMP sensor mounting bolt, then the sensor and O-ring, Fig. 2.
4. Reverse procedure to install, noting the following:
  a. Lubricate O-ring seal with clean engine oil.
  b. Torque mounting bolt to 89 inch lbs.

Crankshaft Position (CKP) Sensor

1. Raise and support vehicle.
2. Remove starter solenoid terminal nut, then the positive battery cable terminal from starter.
3. Remove starter solenoid wire terminal from starter.
4. Remove starter solenoid "S" terminal nut.
5. Remove engine harness terminal from the starter.
6. Remove starter motor bolts, then the starter motor.
7. Disconnect CKP sensor electrical connector.
8. Remove CKP sensor mounting bolt, then the CKP sensor and O-ring, Fig. 3.
9. Reverse procedure to install, noting the following:
  a. Lubricate O-ring with a suitable mineral based grease.
  b. Torque sensor mounting bolt to 71 inch lbs.
  c. Torque starter motor bolts to 30 ft. lbs.

Engine Coolant Temperature (ECT) Sensor

1. Drain coolant system to below ECT sensor level.
2. Disconnect ECT sensor electrical connector.
3. Remove ECT sensor.
4. Reverse procedure to install, noting the following:
  a. Coat threads with sealer GM Part No. 12346004, or equivalent.
  b. Torque sensor to 89 inch lbs.

Heated Oxygen Sensor (HO2S)

Sensor 1

1. Remove exhaust manifold heat shield.
2. Disconnect HO2S electrical connector.
3. Remove HO2S from exhaust manifold.
4. Reverse procedure to install, noting the following:
  a. Coat threads of HO2S with anti-seize compound GM Part No. 12377953, or equivalent.
  b. Torque sensor to 22 ft. lbs.

Sensor 2

1. Raise and support vehicle.
2. Remove drive shaft heat shield.
3. Disconnect HO2S electrical connector in engine compartment. Note routing of HO2S electrical harness for installation reference.
4. Carefully bend edge of channel on lefthand side of exhaust heat shield outboard, just enough to release HO2S electrical harness.
5. Remove HO2S from exhaust pipe, then carefully lower HO2S electrical harness away from underbody.
6. Reverse procedure to install, noting the following:
  a. Coat sensor threads with anti-seize compound GM Part No. 12377953, or equivalent.
  b. Torque sensor to 30 ft. lbs.

Accelerator Pedal Position (APP) Sensor

1. Remove Connector Position Assurance (CPA) cover from APP sensor connector.
2. Disconnect APP sensor harness connector.
3. Remove APP assembly to accelerator pedal assembly attaching bolts.
4. Remove APP assembly from accelerator pedal.
5. Reverse procedure to install. Torque sensor attaching bolts to 80 inch lbs.

Manifold Absolute Pressure (MAP) Sensor

1. Remove air cleaner outlet duct.
2. Remove intake manifold cover.
3. Remove throttle body as outlined under "Throttle Body."
4. Disconnect engine harness electrical connector from MAP sensor.
5. Remove MAP sensor and seal.
6. Reverse procedure to install. Lubricate MAP sensor seal with clean engine oil.

Mass Air Flow/Intake Air Temperature (MAF/IAT) Sensor

1. Disconnect engine harness electrical connector from MAF/IAT sensor.
2. Remove MAF/IAT sensor retaining screws.
3. Remove sensor from air cleaner inlet duct.
4. Reverse procedure to install.

Throttle Body

1. Remove air cleaner outlet duct.
2. Remove intake manifold cover.
3. Disconnect throttle actuator control electrical connector.
4. Remove throttle body bolts attaching bolts, then the throttle body.
5. Reverse procedure to install. Torque throttle body attaching bolts to 89 inch lbs.

Fuel Rail

1. Relieve fuel system pressure as outlined under "Precautions."
2. Remove air cleaner outlet duct assembly.
3. Disconnect fuel line fitting from fuel rail.
4. Disconnect fuel injector harness connectors.
5. Remove fuel rail attaching studs.
6. Pull fuel rail back and upward to remove fuel injectors from cylinder head ports.
7. Rotate fuel rail to position injectors downward, then remove fuel rail.
8. Reverse procedure to install. Torque fuel rail studs to 89 inch lbs.

Wiring Harness & Connector Repair

Wiring Connector Repair

1. Disconnect connector being repaired from its mating half.
2. Cut off existing wire connector directly behind insulator and remove six inches of tape from harness.
3. Stagger cut wires on harness side approximately one-half inch apart.
4. Remove one inch of insulation from each wire on harness side.
5. Stagger cut matching wires on repair connector in opposite order as was done on harness side of repair. Ensure overall length is same as original.
6. Remove one inch of insulation from each wire.
7. Place piece of heat shrink tubing over one side of wire. Ensure tubing will be long enough to cover and seal entire repair area.
8. Spread strands of wire apart on each end of exposed wires.
9. Push two ends of wire together until strands of wire are close to insulation.
10. Twist wires together, then solder connection with rosin core solder. Do not use acid core solder.
11. Center heat shrink tubing over joint and heat using a suitable heat gun. Heat joint until tubing is tightly sealed and sealant comes out of both ends of tubing.
12. Repair wire repair procedure for each wire on the connector.
13. Tape wiring harness starting 11/2 inches from behind connector and two inches past repair.
14. Connect repaired connector.

Wiring Connector Terminal Repair

1. Disconnect connector being repaired from its mating half.
2. Remove connector locking wedge.
3. Position connector locking finger away from terminal while pulling on wire to remove terminal from connector.
4. Cut wire six inches from back of connector, then remove one inch of insulation from harness side of wire.
5. Select wire that best matches wire being replaced.
6. Cut repair wire to correct length and remove one inch of insulation from end of wire.
7. Place piece of heat shrink tubing over side of wire. Ensure tubing will be long enough to cover and seal entire repair area.
8. Spread strands of wire apart on each end of exposed wires.
9. Push two ends of wire together until strands of wire are close to insulation.
10. Twist wires together, then solder connection with rosin core solder. Do not use acid core solder.
11. Center heat shrink tubing over joint and heat using a suitable heat gun. Heat joint until tubing is tightly sealed and sealant comes out of both ends of tubing.
12. Insert repaired wire into connector and install connector locking wedge.
13. Connect connector.

Crankshaft Position (CKP) System Variation Learn

The Crankshaft Position (CKP) system variation learn procedure must be performed when any of the following service procedures have been completed: Engine replacement; control module replacement; crankshaft balancer replacement; crankshaft replacement; CKP sensor replacement.
1. Install a scan tool and monitor ECM for DTCs.
2. If DTCs other than P0315 are set, diagnose those codes first.
3. With a scan tool, select CKP System Variation Learn Procedure.
4. Block drive wheels and set parking brake, do not apply brake pedal.
5. Cycle ignition from Off to On.
6. Apply and hold brake pedal, then start and idle engine.
7. Ensure air conditioning is Off.
8. Vehicle must remain in Park or Neutral.
9. While learn procedure is in progress, release throttle immediately when engine starts to decelerate.
10. Engine control is returned to operator and engine responds to throttle position after learn procedure is complete.
11. Accelerate to Wide Open Throttle (WOT) and release when fuel cut-off occurs.
12. If scan tool indicates that DTC P0315 ran and passed, CKP variation learn procedure is complete.
13. If scan tool indicates DTC P0315 failed or did not run, refer to DTC P0315 .
14. If any other DTCs set, diagnose DTC.
15. Turn OFF ignition for 30 seconds after learn procedure is completed successfully in order to store CKP system variation values in ECM memory.

Fig. 1 ECM removal

Fig. 2 CMP sensor removal

Fig. 3 CKP sensor removal

    Fuel Injection
    ...

    Precautions
    Air Bag Systems Refer to "Air Bag System Precautions" on main menu selection for "Precautions." Battery Ground Cable Prior to service, disconnect battery ...

    See also:

    Chevrolet Cobalt Service & Repair Manual. Idle Speed & Mixture Adjustments
    Idle speed is controlled by the ECM/PCM. No adjustment is required. Curb Idle Speed Curb idle speed is controlled by the ECM/PCM. No adjustment is required. Fast Idle Speed Fast idle speed is controlled by the ECM/PCM. No adjustment is required. M ...

    Chevrolet Cobalt Owners Manual

    Chevrolet Cobalt Service Manual


    Copyright © 2024 www.cheviguide.com - Chevrolet Auto Manuals - 0.005