I have a 94 cherokee sport with the 4.0 with 207k miles on it. This problem just started a couple days ago. It'll turn over and run just fine at idle, but whenever I start driving it shuts down usually within a few seconds with out any stalling or bogging down. Then when I come to a stop and put it in park and shut it off it'll start back up and do the same thing. Just replaced the battery and fuel filter. Alternator is fine and ignition coil doesn't seem to get hot. Anybody have any suggestions on what it could be?

 

Is there anybody with any suggestions?

 

Is there anybody with any suggestions?

 

did you clean your airfilter ?

marc

 

Check the following also:

IACV (idle air control valve)
MAF
Crankshaft position sensor
fuel line pressure

That's where I start when I have bogging issues. Could also be:

Hall-effect sensor/pickup
ignition coil/cap/rotor

See if there's deficiencies in air, fuel or spark first. Air being easiest, like LadyKenai suggested.

Does it do the same thing when you hand-rev the engine in park? or just in gear, driving?

 

It doesn't big down at all. The motor just shuts down. No sputtering or nothing.

 

I should have said, "stalling" but all the same, that's where I'd start, unless an older 4.0 veteran says differently.

 

And only does it while driving. Think it could be ignition coil?

 

Do you have any codes doing the key dance?

It is starting so at some point you have air spark and fuel. Look up symptoms of a bad cps for the obd1 years and see if they match yours.

 

Fuel line pressure is good. Took ignition coil out and looks like it has a couple cracks. Gonna replace that and go from there

 

mine kinda did that but i think it was the security relay. I turned it on and took out the security relay under the glovebox while it was running and that fixed it. Idk if that will help but it did for me. the only thing was that my headlights were blinking and you may not have that problem

 

Replaced the ignition coil, didn't help but it was crackrd anyway. Gonna try replacing the auto shutdown relay and gonna try the security relay thing. From what I can tell the cps is good.

 

Have you checked codes yet ? Key on key off key on key off key on.... count flashes of check engine light left side of dash.

 

If I can remember correctly I think I got 11 and 12

 

Code 11 is ... No crank reference signal detected during engine cranking. Intermittent loss of either camshaft or crankshaft position sensor. Disconnect negative battery cable for at least 15 minutes . Then reconnect it and drive it when it dies see if code comes back... code 12 and 55 are expected.