Circuit/System Verification
NOTE:
This diagnostic assumes the following:
- The battery is completely charged. Refer to Battery Inspection/Test .
- The engine cranking speed is acceptable. Refer to Engine Cranks Slowly .
- There is adequate fuel in the fuel tank.
- Attempt to start the engine. Observe the DTC information with a scan tool. Verify that DTC P0116, P0118, P0335, P0336, P0513, P0601, P0602, P0603-P0606, P062B, P0627, P0628, P0629, P0633, P069E, P1631, P1649, 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 .
- Engine cranking, observe the scan tool Mass Airflow Sensor parameter. The parameter should display greater than 0 Hz.
- If the parameter is not the specified value, refer to DTC P0102 or P0103 for further diagnosis.
- Test the ignition system for spark. Refer to Electronic Ignition System Diagnosis .
- Ignition ON, command the 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: Digital Pressure Gauge.
- The fuel pump may need to be commanded ON a few times, in order to obtain the highest possible fuel pressure.
- DO NOT start the engine for this test.
- 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 range, refer to Fuel System Diagnosis .
- Verify that the following conditions do not exist:
- Collapsed air intake duct to the throttle body
- Restricted air filter element
- Spark plugs for being gas or coolant fouled
- A skewed engine coolant temperature (ECT) sensor-Refer to Temperature Versus Resistance .
- Exhaust system restricted-Refer to Restricted Exhaust .
- Fuel contamination-Refer to Alcohol/Contaminants-in-Fuel Diagnosis .
- 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.
NOTE:
A MAF sensor circuit condition may cause an Engine Cranks But Does Not Run condition without setting a DTC.
NOTE: