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Engine Cranks But Does Not Run



ENGINE CRANKS BUT DOES NOT RUN

DIAGNOSTIC INSTRUCTIONS
- Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
- Strategy Based Diagnosis
- Diagnostic Procedure Instructions

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. The 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 DTCs P0033, P0102, P0171, P0201-P0208, P0230, P0335, P0336, P0340, P0403, P0404, P0443, P0601, P0602, P0603, P0604, P0606, P0607, P060D, P062F, P0641, P0651, P0685, P0689, P0690, P1516, P1682, P2610 are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to diagnose those DTCs. Diagnostic Trouble Code Descriptions
3. Install a spark tester.
4. 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
5. 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 System Diagnosis. Component Tests and General Diagnostics

IMPORTANT: Additional DTCs may set when using the fuel pump output control.

6. Turn OFF the ignition.
7. Install the 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 384-425 kPa (55-61 psi).
- If the fuel pressure is not within 384-425 kPa (55-61 psi), Refer to Fuel System Diagnosis. Component Tests and General Diagnostics
8. 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. Alcohol/Contaminants-in-Fuel Diagnosis
- Inspect the spark plugs. Refer to Spark Plug Inspection. Testing and Inspection
- Test the exhaust system for restrictions. Refer to Restricted Exhaust. Restricted Exhaust
- Engine mechanical conditions such as worn timing chain gears, low compression, etc.-Refer to Engine Compression Test. Testing and Inspection

REPAIR INSTRUCTIONS
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests