Camshaft Position Sensor: Description and Operation

PURPOSE
The camshaft position sensor sends a cam signal to the PCM which uses it as a "sync pulse" to trigger the injectors in proper sequence. The cam signal is passed through the ignition control module. It is not processed in any way.

OPERATION
The PCM uses the cam signal to determine the position of the #1 piston during its power stroke. This allows the PCM to calculate true Sequential Fuel Injection (SFI) mode of operation. A loss of this signal will set DTC P0342.

If the cam signal is lost while the engine is running, the fuel injection system will shift to a calculated sequential fuel injection mode based on the last fuel injection pulse, and the engine will continue to run. The engine can be restarted and will run in the calculated sequential mode as long as the fault is present with a 1 in 6 chance of injector sequence being correct.