First Post --- Trouble with 'just-purchased' Jeep starting

[TheCreeper]

Hi all,

I just purchased a 1994 Jeep Wrangler from my sister-in-law and had the 5 speed rebuilt. I've been driving it for about 2 weeks and went to get the safety/emission inspection done yesterday at lunch. It failed emission for high NOx, but I suspect bad EGR or cat. I will replace those after I fix this problem.
On the way back to work yesterday, it was running fine, then kinda backfired, started missing/stumbling REAL bad. I pulled off the main street into a nice subdivision and pulled over. Looked it over, had my friend come pick me up. He looked at it too (he's a Ford Racing guy) and we couldn't figure it out. So today, I checked the diagnostic codes through the ignition and got nothing. I bought a new CPS and installed it and no change. Only know it will run, but VERY VERY rough and if you give it gas, it will stumble further and die. I checked the Schrader valve on the fuel rail and it sprayed gas until the pressure relieved. Then I tried to start it again and re-checked the fuel rail...fuel had built back up, so that tells me that the pump and filter should be okay. I think it's a timing issue (even though the CPS didn't fix it) and I'm hoping, praying that's it's not the belt/chain (what is in a Jeep, belt or chain?) and hopefully a cheap, easy fix.

Any help is extremely appreciated!

JG

[myjeepsux420]

Is it a 4.0l six? it sounds like your not getting enough fuel pressure. Even though the fuel rail is full, doesn't mean that you have enough pressure. Your jeep doesn't have an EGR, so that wouldn't cause the problem. NOX is caused by high temp. in the combustion chamber. More than likely you have an issue with the cat. converter. Otherwise the TPS might be bad, and that could be the cause of the bad running. How does it idle? rough or normal. As for the timing, it's all take care of by the computer, so I seriously doubt it's out of timing. How many miles are on it? I would start by check the fuel pressure at idle and half throttle. I think you should have like 50 psi at idle. Go buy a haynes manual to check fuel pressure. good luck. Keep us posted

[TheCreeper]

It is a 2.5L 4 banger. It has 130,000 miles. Also, like I said, this just happened. It was running great, then started acting crazy. Me and my friend were both saying either fuel or timing. By seeing gas come out of the valve, I assumed the system was working fine. I do see your point about not getting enough fuel.

Thanks for replying. I will keep you all posted.

JG

[CanaMark]

There is a chain on the 4L, easy job to do. Just takes a long time.

[JEEP1997]

FYI- chain is on the 2.5... When you say, Just started to happen, do you mean going straight down the road and BAM afterfire, missing, etc.... Question, are you sure for starters you don't have bad gas, (h2o getting in the way).... When was the last time you got gas, day before, that day, etc.... I would hold off shot gunning it with parts until a few things are accomplished by process of elimination !!! Be patient and let's put our heads together.... that's my input for now with what we have..... Also, in my opinion - we can't over look the NOX THING... LOSS OF POWER, BACKFIRE, ETC ARE ALL RESULTS OF C/C PROBLEMS... just a thought!!!!!!!

[TheCreeper]

So, I bought a TPS sensor and installed it - no change. Installed new cap, rotor, plugs, and wires - no change. Put two gallons of gas in from my lawn mower can - PRESTO! Runs like a champ.
I am so frickin' pissed at myself, it's unbelievable.
When this first started, my wife asked "does it have gas?", I was like,"Duh, of course, it has gas, it's showing a quarter tank right now".

I am King Dumba$$.

Out of gas. Geesh, honestly, I just about cried when it fired up (but relieved!)

A hundred bucks for a tank of gas. At least the parts I replaced - I know are good!

Thanks for the replies and help and now I have to get a new cat. and get it welded in for emission test.

As far as the Jeep goes, here's the rundown. It's a 1992 Wrangler and it was my sister-in-law's (but my father-in-law still held the title). She comes in town for Father's Day. When she's heading out Sunday night, she calls from outside of Katy (we live in Houston) and says her Jeep's acting weird. I drive out to where she is and look at it and drive it. The tranny's making very dangerous noises. So we call a tow truck and have it dropped off at a local tranny shop. I go ahead and drive her back to Austin. My father-in-law called me the next day and asked if I could call the transmission shop. They said the clutch was bad. $650 for new one - I thought --- not bad. They said it could be picked up later in the day. I called later and they said that it still would not run and they were going to remove the transmission the next day and call me back. Turns out 5th gear was SHOT and other stuff. They quoted $3000 for a rebuild. My father-in-law was not going to pay it and was actually going to just leave it with them. I said I would buy it from him for what he had in the clutch. So I bought the Jeep for $650 and found this friend of a friend who rebuilt the transmission for $700.
Not a bad deal. I just have to remember to keep it filled with gas!

[JEEP1997]

I Promise Not To Tell Creeper.... Nah, We All Have Our Days!!!!! Glad You're Back On The Road
Kevin