Jeep 4 liter guru\'s

[matt]

Trying to help a buddy out that has a 4 liter in his 1999 Cherokee.  The problem is runs fine when cool and when it warms up the engine dies and will not refire untill it gets cold.

The fuel pressure is good and if he tries to restart after it dies he doesn\'t have spark untill it is cold again.  From some articles on the internet, he thinks it is the crank sensor.

Has anyone else had the same issue?  What are the likely culprets?  Can they be checked electrically?

Thanks,

Matt

[MrMindless]

ASD or fuel pump relays could be bad and failing when it gets warm.  either CPS could be doing the same (crank and cam, it won\'t run if either is bad).  I\'m pretty sure the 4.0 has both of those.

Of course it could be an ECU that\'s gone south and is shutting down when it gets hot under the hood too.  Those two relays and sensors are where I\'d start looking though.

[fedrusion]

I would put money on the crank or cam sensor. I have had this same problem on a gm 3.8.

[Doppleganger]

the crank and cam pos sensors are easy to change, probly do them first.  Has anyone hooked up a scantool to see if it\'s throwing any codes?

[Dragon]

Can\'t remember, but does it have a pickup coil in the distributor?  the wife\'s Dodge Shadow had this same problem...replaced the pickup coil and good-to-go

[MrMindless]

The Magnum series Mopar V6s and V8s use the hall effect picup coil in the distrib as the cam position sensor.  I don\'t know if the 4.0 I6 goes the same route but it\'s as likely as not.