Matthew R.

I have a 97 Grand Cherokee limited with the L6, automatic, all time all wheel drive.
It over heated on me and stalled. Now I can get it to crank over, and everything sounds right, but it won't fire. It has never had a problem with starting, it has always started quickly. I need some input as to what could be the issue.

dave1123

It could be the overheat melted something electrical. How hot did it get? Did it die on the road or idling?

Matthew R.

It got pretty hot. Died on the road. Like I had said, it cranks over fine and sounds good. It actually sounds like it wants to start. (Almost catches)

Matthew R.

If I hold the gas petal to the floor when cranking the engine, it almost fires. I was able to test the crankshaft position sensor lead. The center pin gives me a reading of about 1.5 ohms, but I don't get any readings from the other 2 pins. I am wondering if it may be a problem with the camshaft sensor.

dave1123

Somewhere on this forum is an explanation of the pin-out values for the CPS. There is also a pulse rate test. If you are familiar at all with electronics, the CPS is a Hall-effect switch actuated by the magnetic inserts on the torque convertor drive plate. One pin should be B+ (about 5 volts), one should be pulse out, and one should be ground.

The Crankshaft position sensor detects cylinder position, the camshaft sensor tells the PCM which cylinder to fire.

WAIT! Your 97 still has a distributor, right? In that case, the cam sensor just tells the coil to fire.