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 battery is completely charged. Refer to Battery Inspection/Test in Engine Electrical. |
• | The engine cranking speed is within specifications. Refer to Engine Cranks Slowly in Engine Electrical. |
• | There is adequate fuel in the fuel tank. |
Test/Inspect for the following conditions:
• | Fuel contamination. Refer to Alcohol/Contaminants-in-Fuel Diagnosis . |
• | Proper idle air control (IAC) operation. Refer to Idle Air Control (IAC) System Diagnosis . |
• | Intermittent conditions. Refer to Intermittent Conditions . |
The number below refers to the step number on the diagnostic table.
Step | Action | Values | Yes | No | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the Diagnostic System Check-Engine Controls? | -- | Go to Step 2 | |||||||||||||||
2 |
Does the scan tool display DTC P0336, P0601, P0602, P1621, P1626, P1630, P1631 or P1632? | -- | Go to Step 3 | |||||||||||||||
Does the CKP activity counter increment while cranking the engine? | -- | Go to Step 4 | ||||||||||||||||
4 |
Important: Ensure the fuses listed below are not open, before proceeding with this test.
Does the test lamp illuminate on both sides of all the fuses listed? | -- | Go to Step 5 | |||||||||||||||
5 | With a scan tool, command the fuel pump ON. Does the fuel pump turn ON? | -- | Go to Step 6 | |||||||||||||||
6 |
Is the fuel pressure within the specified range while the fuel pump is operating? | 364-405 kPa (53-59 psi) | Go to Step 7 | Go to Fuel System Diagnosis | ||||||||||||||
7 |
Important: Not grounding the ICM assembly, may cause erratic spark. Does the spark tester spark on all cylinders? | -- | Go to Step 8 | |||||||||||||||
8 |
Does the test lamp blink while the engine is cranking? | -- | Go to Step 9 | |||||||||||||||
9 | Inspect for the following conditions:
Did you find and correct the condition? | -- | Go to Step 10 | Go to Diagnostic Aids | ||||||||||||||
10 |
Does the engine start and continue to operate? | -- | Go to Step 11 | Go to Step 2 | ||||||||||||||
11 |
Are any DTCs displayed? | -- | Go to Step 12 | |||||||||||||||
12 | With a scan tool, review the stored information, Capture Info. Does the scan tool display any DTCs that you have not diagnosed? | -- | System OK |