Been a mechanic for quite some time. This one is bugging me. I have a 1993 Grand Cherokee Laredo, it will stall at random times. Hot or cold, day or night, high elevation, under water, it doesn't matter. One particular morning I linked up with some Jeep buddies and were going to go wheeling. It stalled six times in the parking lot, took various time until it started back up. Finally it started and we decided to head out. I was hill climbing, flying threw mud, slow creeping in low and ran like a champ. I go to start it the next mornning and fires right up. About halfway to work it stalls on the highway going 70. Started right back up stalled 15 minutes later. Cranked for five minutes, started up and has stalled since. I have changed ECM within a year, fuel pump within a year, fuel filter last week, fixed vacuum leaks. Dealership is worthless. Any help would be greatly appreciated. Thank you very much.

 

Failing CPS?

I was thinking PCM as 93 was a rough year for them till i saw you changed it already.

Do you have a security icon flashing at all while running?

Try swapping the asd relay with another one, could be failing also.

 

Did you try to replace the EGR valve? That might be the culprit too. If it's sticking it would cause the vehicle to stall or lurch forward at a stop sign or set of lights.

 

If it is the 4.0, it doesn't have an EGR valve. I would take a look at the crank sensor, they are kind of a wear item on Jeeps, kind of like tires.

 

I will change the crank sensor and see what happens. I have all manual doors and windows so the security system shouldnt be an issue correct. It doesn't have one. Thanks for the advice, It is a 4.0 without an EGR valve.

 

I changed the CPS and the Auto Shutdown Relay and it seemed to have solved the problem. It has been going strong for over 300 miles. That is a record. Thank you to all for your help and advice.

 

next time it stalls detewrmine if its fuel or spark