Diagnostic Aids

A missing CMP sensor signal may cause a long crank condition. The CKP signal must be available for engine to start. The CMP signal is not needed to start and operate engine. The PCM can determine when a cylinder is on either firing or exhaust stroke by 24X signal. Remove any debris from PCM connector surfaces before servicing PCM. Inspect PCM connector gaskets when diagnosing or replacing PCM. Ensure that gaskets are installed correctly. The gaskets prevent water intrusion into PCM.