AdriansXJ

This will be pretty long, my introduction, Jeep description and my problems. I'll separate the paragraphs to skip the extra and get to the problem if you don't want to read it all.

So I bought a 1995 Jeep Cherokee Sport 4x4 with the 4.0 H.O.. It has 180,0xx miles the interior is ok, other than headliner sagging, the steering wheel looks horrible due to someone removing the air bag, the plastic covering the column is gone, and it smells like oil base mud from my boots in there in the heat closed up for a couple weeks. There's a bad rust spot under the passenger floor board, when driving over 20 mph the carpet flexes with the wind. Other than the things listed its really decent, especially for being a $500 beater that wasn't supposed to run, but was driven 15 miles with 5 gallons of gas and a boost. A/c even works!

My problems started that day, though. I put some gas in, boosted it, and it idled ok, the cat converter was clogged, I cut the whole exhaust half an inch before the cat, now it will rev past 2700rpm. Needs a new exhaust system, got that problem solved.

Temperature,

I read that its supposed to be at 210, it ran the mark above 210 never in the red. Bought a new thermostat, broke the housing tightening it down too hard, replaced the housing. Ran cooler, but not operating temp. Flushed the radiator, now its a hair below 210, always.

Idle, missing, sputtering at operating temp.

Jeep runs like a top, loud as hell because I haven't replaced the exhaust yet, all until it reaches operating temp. If I'm driving it when I hit the brakes and come to a stop the RPMs will drop to 200 or so, and then stall if I don't keep my foot on both pedals. When taking off from a stop it sounds like its missing really bad and has absolutely no power. While driving at 55mph it seems to miss again and lugs down and it will downshift to get back up to speed with cruise on. I haven't checked the plugs, forgot when checking the rotor and cap(pretty stupid to check the ignition system and forget to check the plugs, but I don't see the plugs making it do this only at operating temp) Soon, tomorrow or the next day I will pull them and check, but I doubt that's the problem. I just don't know what to do with it anymore.

I'm starting to think a complete over haul and a new computer, just wanting to rule out anything else that could be the problem before I dump a bunch of money into it. If anyone could help, please let me know! I'm ready for it to run right so I can take it on some trails!

belvedere

Personally, I would start with a good tune-up, something like Techron in the tank, and if you think it might need an overhaul, do a compression test.

rackem

a good tune up,

new gas...

but it does sound like you are describing a vacuum leak..

Bedo61

I had the same problem the other day. I had to keep my foot on the gas and brake to keep it from dying.

Took it to autozone because the ENG light came on. Large emissions leak. Took it to local shop and I had a large crack on my exhaust manifold. Hopefully replacing the manifold fixes the problem. I'll let u know if it does I pick it up tomorrow from the shop.

I did try the tune up and replaced plugs. Old ones looked good. Put the techron gas treatment in hopes of fixin prior to me knowing about the manifold so hopefully it's all for the better.

1999 XJ 4.0.

Bedo61

So far so good. Idle is awesome. Good throttle response now. Light isn't on anymore.