okay, i need someone's help. I have a 95 xj country 2wd. 150k miles. It has been running perfect until about a week ago. It started making a loud "bumping" or "popping" noise from the back end I thought it may have something to do with the exhaust. Took it to the shop and the cat was clogged up. So I had that done as well *** changed the plugs, wires, air filter, and the oil and filter. I also checked the rear end to make sure it wasn't low on fluid and it was good. But my problem still exist. when i first start driving it drives fine. but as you continue the noise comes back and the truck seems to loss power and it seems to take longer to shift gears. No check engine lights are on and when i had the truck scanned no codes came back.
so now I'm asking for help so.... HELP PLEASE!!!!!!!!!

 

Have you had your fuel pressure checked? the popping sounds like a misfire . Sounds like you have covered all of the other bases, exhaust, tune up etc. Low fuel pressure would cause power loss and engine misses. How about fuel filter?

 

that was my next fix. I was gonna do that in the morning. was just trying to get other peoples opinions on what it could be. But thanks alot man.

 

Thanks guys, changed the fuel filter and my xj runs great now. Thanks alot