bradpoorman

Okay, I've been having this problem with my xj for quite some time now and I am having a hard time finding out what exactly the problem is. Now before I get started this problem mainly happens when I leave my Jeep idle for longer than 5 minutes or when I turn it off and on too many times (like when I have running around to do). Regardless of how much gas I have in it if I leave it idle for longer than a few minutes it starts to idle rough and then it gets worse and worse and eventually shuts off. Like I said before also if I turn it off and back on too many times it does this as well. When I go under the hood and check the fuel rail one of two things happens, either I let just straight air out of my fuel rail or a combination of fuel and air. I was reading in another post about possibly vapor lock? also I changed my fuel pressure regulator not too long ago and that helped for about a month and now its doing it again. Any ideas? It would be greatly appreciated.

posjeepxj

i think your fuel pump has back flow (its busted) ie it lets gas seep back instead of holding pressure to the rail.

or i could be wrong

bradpoorman

That very well could be I didnt really put too much thought into the fuel pump. I don't know either if I never took notice to it or what but I can hear the fuel pump running on and off a lot when it is idling.