Engine Cranks But Does Not Run
ENGINE CRANKS BUT DOES NOT RUN
DIAGNOSTIC FAULT INFORMATION
IMPORTANT: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Testing and Inspection
CIRCUIT/SYSTEM DESCRIPTION
This Engine Cranks but Does Not Run is an organized approach to identify a condition which causes the engine to crank but not start. This diagnostic directs the technician to the appropriate system diagnosis.
This diagnostic assumes the system voltage levels are adequate for starter motor operation. Refer to Battery Inspection/Test, and Engine Cranks Slowly. Fuel level and fuel quality should be determined for correct diagnosis. Battery Inspection/Test Engine Cranks Slowly
CIRCUIT/SYSTEM VERIFICATION
Attempt to start the engine. Engine should start and run.
CIRCUIT/SYSTEM TESTING
1. Crank the engine for up to 30 seconds.
2. Observe the Engine 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 Diagnostic Trouble Code Descriptions
3. Observe the engine speed parameter while cranking the engine.
- If engine rpm is not indicated, refer to Electronic Ignition (EI) System Diagnosis. Electronic Ignition (EI) System Diagnosis
4. Install a spark tester.
5. Crank the engine for 15 seconds. Spark should be observed from the Spark Tester.
- If spark is not observed refer to Electronic Ignition (EI) System Diagnosis. Electronic Ignition (EI) System Diagnosis
6. With the ignition ON and the engine OFF, test the fuses that are supplied by the powertrain relay for voltage. The test lamp should illuminate at each test point for the following fuses:
- Emission Fuse
- Ignition 1 Fuse
- If the testlamp does not illuminate on at least one side of each fuse refer to DTC P0685. P0685
7. 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. Component Tests and General Diagnostics
IMPORTANT: Additional DTCs may set when using the fuel pump output control.
8. Turn OFF the ignition.
9. Install the J 34730-1A J 34730-1A Fuel Pressure Gage. Turn ON the ignition and command the fuel pump ON while observing the J 34730-1A. The fuel pressure should be between 380-410 kPa (55-60 psi).
- If the fuel pressure is not within 380-410 kPa (55-60 psi) refer to Fuel System Diagnosis. Component Tests and General Diagnostics
10. Inspect for the following conditions:
- Compare the actual engine coolant temperature to the ECT parameter. Refer to DTC P0125. P0125
- Air filter and air intake system for restrictions and obstructions
- Test the fuel for contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool). Alcohol/Contaminants-in-Fuel Diagnosis
- Inspect the spark plug and spark plug wires. Refer to Spark Plug Inspection. Testing and Inspection
- Test the exhaust system for restrictions. Refer to Restricted Exhaust. Restricted Exhaust
REPAIR INSTRUCTIONS
IMPORTANT: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests