Engine Cranks But Does Not Run

Engine Cranks but Does Not Run

Diagnostic Instructions

* Perform The Diagnostic System Check - Vehicle 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

Special Tools Required

CH-48027 Digital Pressure Gage

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 any of the following DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle to diagnose those DTCs P0201-P0208, P0230, P0335, P0336, P0340, P0403, P0404, P0601, P0602, P0603, P0604, P0606, P0607, P060D, P062F, P0641, P0651, P0685, P0689, P0690, P1516, P2610. Diagnostic Trouble Code Descriptions P0201 P0208 P0230 P0335 P0336 P0340 P0403 P0404 P0601 P0602 P0603 P0604 P0606 P0607 P060D P062F P0641 P0651 P0685 P0690 P1516 P2610

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

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

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

6. Turn OFF the ignition.
7. Install The CH-48027 Fuel Pressure Gage. Turn ON the ignition and command the fuel pump ON while observing The CH-48027.

• 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.
* Inspect the spark plugs.
* Test the exhaust system for restrictions.
* Engine mechanical conditions such as worn timing chain gears, low compression, etc.-Refer to Engine Compression Test. Testing and Inspection

Repair Instructions

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