Camshaft Position Sensor (3.4L)

The Camshaft Position (CMP) sensor is located at top of timing cover, behind water pump. As camshaft sprocket turns, a magnet activates Hall Effect switch in CMP sensor. This signal is generated whenever cylinder No. 1 is at TDC of its compression stroke.

This signal is used by PCM to indicate the position of No. 1 piston during its intake stroke. This allows the PCM to calculate true Sequential Fuel Injection (SFI) mode of operation. If sensor should fail while engine is running, engine will continue to run using the last calculated CMP sensor signal to maintain SFI mode. Upon restart, engine will run as long as fault is present with a 1-in-6 chance of injector sequence being correct.