I agree with Blue. The serp belt and power steering pump will have to be removed, then the CMPS is right there (on the 3100). One bolt securing it to the engine block and a wiring harness. If your car has the 3800, the CMPS is in the timing cover (relatively simple to change) but it could also be the interrupter magnet in the cam gear that is causing this code. Replacing it requires the timing cover and cam gear to be removed from the engine, which is a major repair.