*ENGINE CRANKS BUT WILL NOT START
For a complete wiring diagram Refer to Section 8W
| Possible Causes |
| CAMSHAFT POSITION SENSOR SIGNAL PROBLEM |
| CRANKSHAFT POSITION SENSOR SIGNAL PROBLEM |
| ECM CODES PRESENT |
| ECT SENSOR |
| ENGINE CONTROL MODULE |
| ENGINE DRIVE BELT/CHAIN |
| FUEL PRESSURE - CRANKING |
| FUEL SUPPLY CONTAMINATION |
| FUEL SYSTEM RESTRICTION |
| GLOW PLUGS |
| SKIM CODES PRESENT |
Diagnostic Test
1. ECM CODES PRESENTNOTE: The ECM must have proper power and ground connections for the following tests to be valid. Refer to Checking the ECM Power and Grounds in the symptom list.
Turn the ignition on.
With the scan tool, read the ECM DTCs.
Does the scan tool display any ECM DTCs?
Yes
- Refer to symptom list for problems related to ECM DTC.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Go To2
2. SKIM CODES PRESENT
With the scan tool, read the SKIM DTCs.
Does the scan tool display any SKIM DTCs?
Yes
- Refer to symptom list for problems related to SKIM DTC.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Go To3
3. ECT SENSOR
Using a temperature probe, check the vehicle temperature near the ECT Sensor.
With the scan tool in Sensors, read the ECT Sensor temperature.
Compare the temperature probe reading with the scan tool reading.
Are the two readings within 10°C of each other?
Yes
- Go To4
No
- Repair as necessary.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
4. GLOW PLUGS
NOTE: Prior to performing this test, be sure to check the Glow Plug Relay operation. Refer to CHECKING GLOW PLUG OPERATION for the related symptom(s).
Refer to the Service Information and check the Glow Plugs for proper operation.
Are the Glow Plugs operating properly?
Yes
- Go To5
No
- Repair as necessary.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
5. FUEL SYSTEM RESTRICTION
Inspect the fuel system lines for restrictions, leaks or other problems.
NOTE: Refer to the Service Information to ensure that the fuel system is properly primed. An unprimed system or excessive air in the supply system will cause a no-start condition.
Is there any evidence of problems?
Yes
- Repair as necessary.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Go To6
6. CAMSHAFT POSITION SENSOR SIGNAL PROBLEM
Turn the ignition off.
Attempt to start the engine, if the engine will not start, crank the engine for several seconds while monitoring the scan tool.
With the scan tool, read the Cam Position Sensor RPM.
Does the scan tool display a steady CMP Sensor RPM approximately one half the speed of Engine RPM?
Yes
- Go To7
No
- Using the Service Information, check the wiring and connectors related to the CMP Sensor. If o.k., replace the CMP Sensor.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
7. CRANKSHAFT POSITION SENSOR SIGNAL PROBLEM
Turn the ignition off.
Attempt to start the engine, if the engine will not start, crank the engine for several seconds while monitoring the scan tool.
With the scan tool in Sensors, read the Engine RPM.
Does the scan tool display a steady CKP Sensor RPM approximately double the speed of the CMP RPM?
Yes
- Go To8
No
- Using the Service Information, check the wiring and connectors related to the CKP Sensor. If o.k., replace the CKP Sensor.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
8. FUEL PRESSURE - CRANKING
Turn the ignition on.
With the scan tool, read the Fuel Pressure Sensor signal while cranking the engine for 15 seconds.
NOTE: Fuel pressure should increase above 3400 psi (240 bar) after only a few seconds of cranking.
Does the fuel pressure increase above 3500 psi (240 bar) after a few seconds of cranking?
Yes
- Go To9
No
- refer to Symptom CHECKING THE HIGH-SIDE PRESSURE.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
9. FUEL CONTAMINATION
Refer to the Service Information and inspect the fuel supply for contamination.
Is the fuel contaminated?
Yes
- Refer to the Service Information to remove and replace fuel throughout the fuel system.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Go To10
10. ENGINE DRIVE BELT/CHAIN
Refer to the Service Information to ensure the Engine Drive Belt/Chain is installed correctly and the camshaft and crankshaft gears are timed correctly.
Were any problems found?
Yes
- Repair as necessary.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).
No
- Replace and program the Engine Control Module in accordance with the Service Information.
- Perform the ECM Verification Test Ver. 1 (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).