With Standard Model (Non-Alternative Fuels)

Engine Cranks But Does Not Run

Description

The diagnostic table identifies a condition that causes an engine to not start. The diagnostic table directs the service technician to the appropriate system diagnosis. The diagnostic table assumes the following conditions are met:

- The battery is completely charged.
- The engine cranking speed is within specification.
- There is adequate fuel in the fuel tank.

Diagnostic Aids

Inspect for the following conditions:

- The mass air flow (MAF) is compared to a calculated mass air flow based upon the manifold absolute pressure (MAP), the throttle position (TP), and the engine RPM. A skewed or unresponsive MAP sensor at key on will cause the predicted air flow value to be inaccurate. Compare the MAP and TP readings to that of a known good vehicle.
- A faulty engine coolant temperature (ECT) sensor. Use a scan tool in order to compare the ECT with the intake air temperature (IAT) on a completely cooled engine. The ECT should be within 3°C (5°F) of the IAT.
- For an intermittent condition.

Test Description

The number below refers to the step number on the diagnostic table.

5. This step verifies the IGN relay for proper operation. The IGN relay supplies voltage to the injectors and to the ignition coils. When the IGN relay is not operating properly, a no start condition occurs. If the test lamp does not illuminate, this indicates the IGN relay is not suppling a voltage to the fuses.