Circuit/System Testing
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- Read and record the Freeze Frame/Failure Records data taking note of the speed and load at which the DTC set.
- Diagnose any other DTCs that are set. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- With the engine idling and the transmission in the Park or Neutral position, observe the manifold absolute pressure (MAP) sensor parameter. The MAP sensor parameter should be between 19-42 kPa.
- If the MAP sensor parameter is not between 19-42 kPa, refer to DTC P0106 or DTC P0107 or P0108 .
- Inspect the air induction system for modified, damaged, leaking, or restricted components.
- Inspect the crankcase ventilation system for improper operation.
- Inspect the vacuum hoses for splits, kinks, and improper connections.
- Inspect for vacuum leaks at the intake manifold, the throttle body, and the injector O-rings.
- Test for a restricted, damaged, leaking, or modified exhaust system from the catalytic converter forward. Refer to Symptoms - Engine Exhaust .
- Test the fuel injectors for improper operation. Refer to Fuel Injector Diagnosis (w/CH47976) or Fuel Injector Diagnosis (w/J39021 or w/Tech 2) .
- Test for fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis (without Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) .
- Test for excessive fuel in the crankcase due to leaking injectors.
- Test the ignition system for improper operation. Refer to Electronic Ignition (EI) System Diagnosis .
- Test the engine for any mechanical conditions such as sticking valves, lifters, etc., which could alter the flow into the combustion chamber. Refer to Symptoms - Engine Mechanical .