A 1997 Plymouth Grand Voyager, the service engine light comes on occasionally when the car dies when idling by a light. Better gas was purchased and the light went on while driving at like 30mph rpms fell but didn't die service engine light came on. Code suggests the cam position sensor is bad. Done some checking and perhaps it could be the timing belt, or another sensor for the cam. The cam sensor seems like it might solve the problem? I'm not sure enough to replace it for 40.00 some dollars. I've search on line and people have had similar problems and replaced it and that was just one of the many things they needed to replace before they found the actual problem.
How do you check the car or part to confirm the cam position sensor is bad before replacing?

What code was stored?
Did following that code's diagnostic trouble tree lead to recommending the Cam Position Sensor (CMP) be replaced?
How old is your timing belt? That may also be ready for routine service, too.