Circuit/System Testing
- Crank the engine for up to 30 seconds.
- Observe the vehicle DTC information with a scan tool.
- If any of the following DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle : P0201-P0206, P0335, P0336, P0351-P0353, P0601, P0602, P0604, P0685, P1516, P2610.
- Observe the engine speed parameter while cranking the engine.
- If engine RPM is not indicated, refer to DTC P0335 .
- Install a J 26792 HEI Spark Tester. See Special Tools .
- Crank the engine for 15 seconds. Spark should be observed from the J 26792
HEI Spark Tester. See Special Tools
.
- If spark is not observed refer to Electronic Ignition (EI) System Diagnosis .
- With the ignition ON and the engine OFF, test the fuses that are supplied by the powertrain relay for voltage.
- If the test lamp does not illuminate on at least one side of each fuse refer to DTC P0685 .
- Command the fuel pump ON and OFF. Fuel pump should energize when commanded ON, and de-energize when commanded OFF.
- If the fuel pump does not respond, refer to Fuel Pump Electrical Circuit Diagnosis .
- Turn OFF the ignition.
- Install the CH-48027
Digital Pressure Gage. See Special Tools
. Turn ON the ignition and command the fuel pump ON while observing the CH-48027
. See Special Tools
. The fuel pressure should be between 384-425 kPa (56-62 psi).
- If the fuel pressure is not within 384-425 kPa (56-62 psi), refer to Fuel System Diagnosis .
- Inspect for the following conditions:
- Compare the actual engine coolant temperature to the ECT parameter.
- Air filter and air intake system for restrictions and obstructions
- Test the fuel for contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis (With Special Tool) .
- Inspect the spark plug and spark plug wires. Refer to Spark Plug Wire Inspection and Spark Plug Inspection .
- Test the exhaust system for restrictions. Refer to Restricted Exhaust .
IMPORTANT:
Additional DTCs may set when using the fuel pump output control.