Circuit/System Verification
NOTE:
This diagnostic assumes the following:
- The battery is completely charged. Refer to Battery Inspection/Test (Acadia or Enclave) or Battery Inspection/Test (OUTLOOK) .
- The engine cranking speed is acceptable. Refer to Engine Cranks Slowly .
- There is adequate fuel in the fuel tank.
- Crank or start the engine. Observe the DTC information with a scan tool. Verify that DTCs P0116, P0118, P0119, P0335, P0336, P0338, P0351-P0356, P0601, P0602, P0604, P0606, P062B, P069E, P167D, P1629, P1631, P1632, P2105 or U0109 does not set.
- If any of the listed DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Ignition ON, observe the Theft Deterrent parameter with a scan tool. The parameter should display Disabled.
- If Enabled is displayed, refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- Test the ignition system for spark. Refer to Electronic Ignition (EI) System Diagnosis (w/LLT) .
- Ignition ON, command the in-tank fuel pump ON with a scan tool. You should hear the fuel pump turn ON.
- If the fuel pump does not turn ON, refer to Fuel System Diagnosis .
- Ignition OFF, install the CH-48027: Gage. Refer to Fuel Pressure Gage Installation and Removal .
- Ignition ON, command an increase in the fuel line pressure with a scan tool. The fuel line pressure should increase to greater than 410 kPa (60 psi) as commanded.
- If the fuel pressure is not within the specified range, refer to Fuel System Diagnosis .
- Verify that the following conditions do not exist:
- Disconnect the MAF sensor. The engine control module (ECM) will ignore the MAF sensor and default to the calculated air flow.
- If disconnecting the MAF sensor corrects the condition and the connections are OK, replace the MAF sensor. Refer to Mass Airflow Sensor with Intake Air Temperature Sensor Replacement .
- Collapsed air intake duct to the throttle body
- Restricted air filter element
- Spark plugs for being gas or coolant fouled-Refer to Spark Plug Inspection .
- A skewed engine coolant temperature (ECT) sensor-Refer to Temperature Versus Resistance - Engine Coolant Temperature Sensor .
- Exhaust system restricted-Refer to Restricted Exhaust .
- Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (with Special Tool) or Alcohol/Contaminants-in-Fuel Diagnosis (w/o Special Tool) .
- Engine mechanical condition, for example, worn timing chain and gears, low compression-Refer to SYMPTOMS - ENGINE MECHANICAL .
- If you find any of the above conditions, repair as necessary.