Question on a sputter / lurch issue

Joined
Oct 14, 2018
Messages
71
Location
SW Michigan
Hi guys, I got a quick question for you. I have a 97 TJ manual, runs pretty darn good 90% of the time. It's not throwing any codes, no check engine light, anything like that but ... when I've run it for a while, turn it off for a little bit then come back (while the engine is still hot) and start it up again, it sputters and lurches - almost like a misfire. I've kept on it when it does this and it usually takes about 30-45 seconds before it evens out and doesn't do it again for as long as it's still turned on. It hasn't stalled from this, yet, but I'd like to fix it before it does.

I have yet to do a tune up, which I HOPE would solve the issue, but on the off chance that's not all, I would really appreciate some suggestions for what to do next. What's my next most likely culprit? Mass Air flow? O2 sensor? EGR? Camshaft position sensor? Still new to shadetree mechanic work, but not afraid to dig in and give it a shot.
 
Sounds like a misfire issue. Spark plugs, distributor, or rotor possibly.
 
Well I did the tune up on Sunday but didn't get the chance to really drive it around much until today, and I've got the same issue. Looking for some advice on where to go next. Fuel filter? one of a bajillion sensors? Not sure where to start, but I'm sure it'll be just about everything before I'm done. lol
 
Anyone? What years were the ones with the overheating injector issues? Could that be the problem here?
 
see, the thing that gets me is that its only after it gets hot then is turned off for a while. After start up, I get maybe 50 yards or so before it sputters/misfires/whathave you and then after I keep on it, it picks right up and is fine for the rest of the drive.

Seems like if it was overheating injectors, it would happen the whole time the thing is running. Or am I wrong? (I really don't know.)
 
Did you ever get this problem fixed? I have the same issue now with my 97 manual TJ 2.5. New ignition system, fuel pressure is good. Assuming its a sensor somewhere at this point but theres so many to choose from! Heeelp!
 
The TPS seemed to fix it for a while, but in my case, I was also fighting an exhaust leak, it seems. Just changed out my gasket, put in a new exhaust manifold to replace the cracked old one - that I couldn't see was cracked until I got it off. There were also some missing manifold bolts from the job the guy before me did, so that got changed too.

I don't know if it fixed the problem yet, though because I need to replace one of the vacuum lines that I had taken off to do the manifold job. When I went to hook it back up to the front of the header, the hose fitting crumbled in my hand. So. tubing this weekend, then I can try starting it up.

still won't know if it'll be doing the rough run though since that requires a drive and I'm also set to put in an SYE to correct my angles from the 4" lift that they never adjusted for - and the new diff that's going in, I think as a direct result of the bad angles for God knows how long.

Gonna go out on a limb though, and say if it's still rough idling, it'll be an O2 or the MAP.

Sorry I can't be more help there. My lil purple ride was pretty beat around when I got him. Just trying to fix aaallll that mess.