Ok, here's the scoop. I was driving my 1990 cherokee the other day and after about 5 minutes it started sputtering and would only stay running if I floored the pedal. It stalled once or twice and I had to turn around and head home. A few days later I drove it with little to no problems. Today I started it and it stalled after a few seconds and now it won't start. Has anyone ever experienced anything like this?

 

Anyone who has owned a Cherokee for longer than a few years has experienced this. It can be caused by several things but the most likely is a failing crank position sensor (CPS). You have a Renix XJ which means the sensor can be tested using a basic volt/ohm meter. The plug is located near the firewall at the back of the block and, when disconnected and probed from the sensor side, should read between +0.3v and +0.5v AC (pretty sure about that voltage but search first or wait for someone, likely Cruiser, to confirm).

 

I actually went ahead and pulled the crank position sensor wiring apart and reconnected it after a few minutes. This got the jeep to start but the sputtering issue still occured.

 

Last tuneup with plugs, wires, cap and rotor?

Are your intake manifold bolts loose?

What does the vacuum line look like from the throttle body to MAP sensor?

Of my Tips, how many have you completed?

 

Plugs and wires have been changed recently, intake manifold bolts are secure and I couldn't find any cracks in the vacuum line.

 

I would inspect your egr valve if it is not closing right or working properly that could be part of your problem. does the jeep appear to stall easyier while in reverse?

if you take a vaccum line off of the motor half way and the jeep appears to run decent that could be something to look at.

I mean does the jeep fire then die right away when u say not starting?