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
The Engine Cranks but Does Not Run diagnostic table is an organized approach to identifying a condition that causes an engine not to start. The Engine Cranks but Does Not Run diagnostic table directs the service technician to the appropriate system diagnosis.

The Engine Cranks But Does Not Run diagnostic table assumes the following:
- The batteries are completely charged. Refer to Battery Inspection/Test (Non-HP2). Battery Inspection/Test
- The cranking speed is within specifications. Refer to Engine Cranks Slowly. Engine Cranks Slowly
- There is adequate fuel in the fuel tanks.

DIAGNOSTIC AIDS
If the cause of an engine cranks but will not run condition has not been found, inspect for the following conditions:
- Hard starting only in cold ambient temperatures. These may cause an intermittent condition that may not occur in the service bay:
- Fuel heater inoperative-Refer to Fuel Heater Inoperative. Fuel Heater Inoperative
- Ice blockage at the fuel pickup in the fuel tank-This will be a high vacuum in the supply lines while cranking, and the problem will disappear after the vehicle is brought in the service bay. It may also exhibit a start and stall condition or a starting condition with no acceleration.
- The correct cranking speed is 100 RPM cold and 180 RPM hot.
- A basic engine problem
- Low engine coolant may cause the engine to shut down.

CIRCUIT/SYSTEM VERIFICATION
1. If DTCs P0087, P0090, P0191, P0193, P0335, P0336, P0340, P0370, P0374, P0602, P0603, P0604, P0606, P0642, P0643, P064C, P0698, or P0699 are set diagnose those DTCs first.
2. The engine starts and runs.
- If the engine does not start and run perform the Circuit/System Testing.

CIRCUIT/SYSTEM TESTING
1. Inspect for the following conditions:
- Fuel smell or leak
- A plugged air filter collapsed air intake duct
- A restricted exhaust system-Refer to Symptoms - Exhaust System. Symptom Related Diagnostic Procedures
- Contaminants in fuel-Refer to Contaminants-in-Fuel Diagnosis. Contaminants-in-Fuel Diagnosis
2. Observe that the Ignition 1 signal parameter is B+.
- If the ignition 1 signal is not B+ test the ignition 1 voltage circuit of the ECM for a short to ground, high resistance an open, or a faulty ECM.
3. With the ignition ON and the engine OFF observe that the Actual Fuel Rail Pressure parameter is 1.2-1.9 MPa.
- If the Actual Fuel Rail Pressure parameter is not 1.2-1.9 MPa, refer to DTC P0191 - P0193. P0191 P0193
4. Crank the engine for 15 seconds.
- If the Actual Fuel Rail Pressure parameter is less than 10 MPa while cranking the engine, refer to Fuel System Diagnosis. Component Tests and General Diagnostics
5. Perform the Engine Compression Test. Refer to Engine Compression Test. Testing and Inspection
- If any fuel vapor was emitted during the engine compression test, replace the affected fuel injector.

IMPORTANT: During the replacement of the injectors, inspect the inlet and outlet fittings for corrosion or contamination. Refer to Contaminants-in-Fuel Diagnosis. Contaminants-in-Fuel Diagnosis

- If no fuel vapor was emitted during the compression test and the compression tested normal refer to Fuel System Diagnosis - High Pressure Side. Component Tests and General Diagnostics

REPAIR INSTRUCTIONS

IMPORTANT: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

Fuel Injector Replacement (Right) Fuel Injector Replacement (Left)

REPAIR VERIFICATION
The engine starts and runs.