10h. Check Fuel Pulse Width While Cranking

1Oh. Check Fuel Pulse Width While Cranking

Purpose:

The purpose of this test is to verify the fuel delivery signal is correct.

Data List

^ The scan tool may reset below 9.5 volts.
^ Select the parameters indicated from the scan tool parameter list and monitor while cranking the engine.






Recommended Procedure:

^ Connect the scan tool.
^ Key ON engine OFF.
^ Access and monitor the FUEL PW PID while cranking the engine.

No fuel command signal when the ICP RPM and VPWR signals are correct usually indicates a loss of the CMP signal. GO to Pinpoint Test V.

A 5 us to 2 ms fuel pulse width (FUEL PW) is sent to the FICM if the system voltage is greater than 8 volts during cranking engine cranking speed is above 100 RPM injection control pressure is above 3.5 MPa (500 psi) and is in sync. Note that low fuel pressure or no glow plug operation could still be the cause of the no start or hard start condition. A FUEL PW PID of 0 ms (a no fueling pulse) is sent by the PCM when a sync pulse has not been received from the CMP sensor and if insufficient injection control pressure is present.

Possible Causes:

^ PCM
^ FICM
^ CKP signal
^ CMP signal

Tools Required:

Scan tool