95 Grand Cherokee....stalling

[ke4peo]

I've been doing research on the boards, and everything points to either the CPS, PCM, or wiring. But I still have a few questions.

Specs:
1995 Jeep Grand Cherokee Laredo
4.0L I-6
4x2
Auto

Problem: Random stalling. As if the key was turned to the OFF position. If I leave it and come back in a few hours, it starts right back up. What I've notice is, when it stalls, if I try to crank it up I get a 'no spark' condition. Almost as if the PCM is disabling spark.

What I've done:
Remove, clean, reconnect all CPS/CamPS/O2 connectors.
Remove, clean, reconnect PCM connector.

After I did that, it ran fine for 2 days. Then started stalling again.

I'm about to go buy a CPS for it and replace that, but before I did, I ran the Check Engine light trick. I'm getting a Code 11 'No distributor reference signal was detected; check connection between distributor and PCM'.

Could the CamPS be overheating and shorting out? Could it still be the CPS overheating and shorting out? Fuel pump?

	Crank position sensor A crank sensor is a component used in an internal combustion engine to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control ignition system timing and other engine parameters. Before electronic crank sensors were available, the distributor would have to be manually adjusted to a timing mark on the engine.

[dandoc]

Have you checked your distributor at all? If the distributor cap is cracked there can easily be problems. Check for moisture on the interior of the distributor. Make sure the points in the distributor are still good, as well as lacking carbon buildup or other corrosion. Check the wires coming to/from the distributor for tightness and corrosion. I don't know enough about cam position sensors to answer your question; somebody else will have to chime in.

Concerning the fuel pump: when you turn the ignition key to "on" you should hear the pump whine as it builds pressure in the fuel lines (you may need to keep an ear out of the Jeep to hear this, or have somebody else near the fuel tank to listen). If you turn the key to "on" and don't hear the whine, you may have a bad pump. Even so, try starting the engine; it could be a very quiet fuel pump. If the engine starts and you didn't hear the pump turn on, I'd say look elsewhere for the cause of your troubles for the moment.

[ke4peo]

Originally Posted by dandoc

Have you checked your distributor at all? If the distributor cap is cracked there can easily be problems. Check for moisture on the interior of the distributor. Make sure the points in the distributor are still good, as well as lacking carbon buildup or other corrosion. Check the wires coming to/from the distributor for tightness and corrosion. I don't know enough about cam position sensors to answer your question; somebody else will have to chime in.

Concerning the fuel pump: when you turn the ignition key to "on" you should hear the pump whine as it builds pressure in the fuel lines (you may need to keep an ear out of the Jeep to hear this, or have somebody else near the fuel tank to listen). If you turn the key to "on" and don't hear the whine, you may have a bad pump. Even so, try starting the engine; it could be a very quiet fuel pump. If the engine starts and you didn't hear the pump turn on, I'd say look elsewhere for the cause of your troubles for the moment.

I checked the cap and rotor. Points had some build-up on them, but I cleaned them off and they look like new now. It's possible for corrosion on the CamPS sensor, as the wire has a little play in it. But from what I've read, a CamPS sensor failing would allow the car to run until it was shut off.

Fuel pump is good. I hear the whine each time I turn the key on. As well as hearing all the relays click under the hood.

All the posts I can find on GC stalling issues all seem to point to the CPS. I think I'm going to go ahead and replace it since it seems to be a common starting point.

But thanks for the response. :)

	Crank position sensor A crank sensor is a component used in an internal combustion engine to monitor the position or rotational speed of the crankshaft. This information is used by engine management systems to control ignition system timing and other engine parameters. Before electronic crank sensors were available, the distributor would have to be manually adjusted to a timing mark on the engine.

[ke4peo]

Ok, here's the list of items I'm getting for the repair. EVerything I can think of is accounted for based on the Code 11 the PCM is throwing me.

1) Crankshaft Position Sensor
2) Camshaft Position Sensor (i.e. pickup coil)
3) Distributor Cap
4) Rotor

Also grabbing:

Dielectric grease (to regrease all the connector pins on the PCM and connectors)
Torque Wrench

Anyone think of anything I'm missing?

I'm hoping it won't be hard to get to the crankshaft position sensor. I can see it, but can't figure out how to get my beefy hands up in there.