1998 Engine issues...

[jthatcher3478]

I currently own a 1998 Cherokee Sport, 4.0L Straight 6, 4x4. Here's my issue. Everything had been running fine, out of the blue, I would start my jeep in the monring, as I start to leave, about 1 minute or so down the road, she would backfire and basically act as if she's running a cylinder or 2 short. I thought it would work itself out, let it go, nothing happened, not any worse, not any better. I decided to start before I leave and let it warm up, thinking the would take care of the problem, no change. As a matter of fact, while idling, she acts as if she's short on air, has a very hollow, gasping sound. That passes about 45 seconds later and everything is fine. Once the issue passes, the jeep runs normally. Plenty of power, no hesitation, nothing out of the ordinary, except in the begining. Weather change doesn't effect it either. Last week, after having consulted a chilton's for days, I came to the conclusion the problem may be the fuel return, filter, or pump itself. Since it's all one unit, I didn't see an issue in changing. Well, it's still doing it and I'm at my wits end. Any thoughts? TPS? O2? A gerbil in the manifold? what? Any help would be greatly appriciated.

[citizen@large]

Air filter? Vacuum leak? Plugs, Cap, Rotor? Battery cables? Fuel filter? Etc... etc...

Seems like you've got a good head on the shoulders there. So, you'll get the help you need here. Start with this, it's for a no-start issue, but the logic is pretty close: air+fuel+spark=go. - http://www.automotiveforums.com/vbul...d.php?t=687635

I also have a hesitation issue with my '98, but I'm sure it has something to do with the many mods I've made to the intake/exhaust without addressing fuel ratio yet. So I just 'jab' the skinny pedal til she runs right! lol GOOSE!

There is a lot that can be guessed about here based on the info you've given. A few more details like how many miles on the odometer and when the last tune-up happened, etc. will go a long way towards our ability to help you... Don't give up on her yet!

~Good Luck!

PS- This is a great link to troubleshoot/test those "gerbil-like sensors" that are common issues on the 4.0I6... I know you have the HO (high-output '98), but the info is still fairly relevant for troubleshooting. - http://www.lunghd.com/Tech_Articles/...iagnostics.htm

[jthatcher3478]

she's got about 95k on her right now. Maint done on a regular basis. Serpentine belt last changed about 12-18 months ago, plenty of wear left though. Plugs about 6-8 months ago, did the air at same time. Oil done religiously at 3k, filter too. I'm not so much at my wits end with the issue, I just use my remote start and let it work through the problem before leaving. I'm more concerned with the long term damage that may be done. I'm kicking around the idea of it being the TPS, but i'm not sure. Also, what about the catalytic? could some form of a blockage there create a similar issue? Thanks.

[1996Chreokee]

do you hear a rattle in your converter?