Ok, I'm desperate for a definitive diagnosis for my 00 TJ 2.5 AT.
What happened: driving home from work at approx 65 mph, I felt the Jeep stumble a few times like it was missing or something. It recovered for a minute or two then suddenly lost power, sounded like it was backfiring horribly (if I didn't know any better, I'd swear I had flames shooting from my tail pipe based on the sound alone). I pulled over and it was running but barely, I touched the gas pedal and more popping/backfiring, so I shut it off. It has been known to fail to start OR start and run like dog shit after driving a while and shutting it down then restarting within 10 minutes or so. I let it sit for an hour before I ever tried to restart it and only after raising the hood to check for obvious issues. It did not restart and hasn't since.
What I've done so far: checked fluids, fuses, relays, and codes. I had previously been throwing O2 sensor codes and am in the process of replacing them. After I got it home, I had a P0340 and a P0351. The ignition coil went bad last year and was replaced, but I replaced it again along with the camshaft position sensor/pick up coil) and the crankshaft position sensor. I have NO spark whatsoever. Cap and rotor are fairly new as is distributor, and upon inspection, I see no reason to believe that's my issue. Fuses and relays are all good, I'm getting my 5v reference and 5v signal back to the PCM from CKP, I have 45psi at the fuel rail, ASD relay circuit seems fine, checked grounds, wiring harness behind block where I've read it's been known to get damaged, and repaired my CKP connector as one wire was questionable so I figured why not. I've checked and I have voltage at my ignition coil both with key on for a few seconds and then again while cranking the 12v returns and remains while being cranked. My plug wires are within specs when testing resistance, and I feel like I'm chasing my tale. I replaced my time chain last year, and I don't hear it slapping around in there so I don't think that's my issue. I have occassional sticky ignition syndrome where if I don't wiggle the key just right before starting, it will start but I have no accessories like radio or AC and the airbag light stays on, it's fixed by shutting it off, jiggling the key and restarting. This happened a handful of times in the past year and has never been the cause of a no start condition. I have considering replacing the ignition in its entirety and then the distributor itself but I can't keep throwing parts at it. I've put well over $1000 in it in the last 2 months. Several people have said my PCM is bad.
Work that has been done recently that I feel is unrelated but worth mentioning: 4 days before this happened, I pulled it out of my garage after rebuilding my rear differential (super proud of that success, btw, as everyone said I couldn't because I'm a girl), a month before that I replaced the exhaust manifold for the second time in 4 months as it backfires due to some kind of vapor lock and cracked the new one, also I've recently put in a sound system, replaced AC control module, blower motor and resistor, radiator, idler pulley, alternator, battery, motor and transmission mounts, and I think thats it but I might be forgetting something. Again, I don't feel any of that is pertinent but I figured I'd mention just in case.
Sorry for the novel, but I don't want to waste anyone's time by not explaining everything.
Thanks in advance for your time.
What happened: driving home from work at approx 65 mph, I felt the Jeep stumble a few times like it was missing or something. It recovered for a minute or two then suddenly lost power, sounded like it was backfiring horribly (if I didn't know any better, I'd swear I had flames shooting from my tail pipe based on the sound alone). I pulled over and it was running but barely, I touched the gas pedal and more popping/backfiring, so I shut it off. It has been known to fail to start OR start and run like dog shit after driving a while and shutting it down then restarting within 10 minutes or so. I let it sit for an hour before I ever tried to restart it and only after raising the hood to check for obvious issues. It did not restart and hasn't since.
What I've done so far: checked fluids, fuses, relays, and codes. I had previously been throwing O2 sensor codes and am in the process of replacing them. After I got it home, I had a P0340 and a P0351. The ignition coil went bad last year and was replaced, but I replaced it again along with the camshaft position sensor/pick up coil) and the crankshaft position sensor. I have NO spark whatsoever. Cap and rotor are fairly new as is distributor, and upon inspection, I see no reason to believe that's my issue. Fuses and relays are all good, I'm getting my 5v reference and 5v signal back to the PCM from CKP, I have 45psi at the fuel rail, ASD relay circuit seems fine, checked grounds, wiring harness behind block where I've read it's been known to get damaged, and repaired my CKP connector as one wire was questionable so I figured why not. I've checked and I have voltage at my ignition coil both with key on for a few seconds and then again while cranking the 12v returns and remains while being cranked. My plug wires are within specs when testing resistance, and I feel like I'm chasing my tale. I replaced my time chain last year, and I don't hear it slapping around in there so I don't think that's my issue. I have occassional sticky ignition syndrome where if I don't wiggle the key just right before starting, it will start but I have no accessories like radio or AC and the airbag light stays on, it's fixed by shutting it off, jiggling the key and restarting. This happened a handful of times in the past year and has never been the cause of a no start condition. I have considering replacing the ignition in its entirety and then the distributor itself but I can't keep throwing parts at it. I've put well over $1000 in it in the last 2 months. Several people have said my PCM is bad.
Work that has been done recently that I feel is unrelated but worth mentioning: 4 days before this happened, I pulled it out of my garage after rebuilding my rear differential (super proud of that success, btw, as everyone said I couldn't because I'm a girl), a month before that I replaced the exhaust manifold for the second time in 4 months as it backfires due to some kind of vapor lock and cracked the new one, also I've recently put in a sound system, replaced AC control module, blower motor and resistor, radiator, idler pulley, alternator, battery, motor and transmission mounts, and I think thats it but I might be forgetting something. Again, I don't feel any of that is pertinent but I figured I'd mention just in case.
Sorry for the novel, but I don't want to waste anyone's time by not explaining everything.
Thanks in advance for your time.