1988 Cherokee with the 4.0. I had the Giant fuel leak last week and got that fixed by replacing the o ring on the pressure regulator. It started just fine after that and I ran it for 10 min or so to make sure it didn't leak.

4.0, fuel injected


Next day the wife took it to work and said it was kinds sluggish but made it about 15 miles to work.

The jeep did not make it back. I had to have it towed back home.

I've changed the fuel filter and looked at every thing I had apart and its all OK.

It will start just fine and runs for about 30 seconds and then idles down and dies. Some times it acts like its going to die and revs back up abit and then dies. If you try to open up the throttle it dies right away.


Any Ideas??

 

do you have a fuel pressure gauge you can hook up to it?

 

sounds like somethings plugged or not pumping.

 

I do not. But.. there is a fuel pressure test port on the fuel rail. It looks like a tire valve stem. when the engine is running I can push that in and it squirts out fuel. Squirts, not dribble, and just when it gets ready to die I can push it in and it still squirts out fuel so I'm thinking the fuel pump is OK.

I could be wrong.

 

BTT

 

are there any broken vacuum lines or cracked ones

 

Not that I could find. I checked all the lines and double checked every thing and it all looks OK.

Could this be a bad sensor of some sort??