ZeeJay97 add this to your easy no cost sticky list too .
If you are blowing fuses and your jeep acts crazy then crawl under your Heep and look at your O2 sensor wires and make sure that they are not worn through from friction/rubbing and grounding out somewhere .
A little history on my problem:
It used to only sputter driving up big hills at high elevation, but never stalled. Reaplaced plugs, wires & dist cap and no issues for a few months. Then the gauges went haywire would die and then come back, check engine light came on. A few days later car died, so had AAA tow to the dealership. They said it was voltage regulator in the ECU, so got new ECU. Gauges work now, no issues for about 3 or 4 days. Then car started sputtering and stalling....possibly the initial sputtering issue had just gotten worse. Took it to my local shop, tried crankshaft position sensor, but it sputtered within 10 minutes of leaving that shop, so returned that part and got a refund. Mechanic thought it was probably the O2 sensors, so replaced those. Worked for about 3 days. Then on a trip down to Hollister last weekend, after about 80 miles of driving it starts to sputter (not at high altitude this time). 10 more miles and it stalls completely. Had to wait about 10 minutes before it would start again. I made it all the way back, about 100 miles and stalled about 4 times on the way home. A few of them on the freeway. It does seem to do it more often when I'm going slow, but does it also at high speed.
So now I'm investigating and trying to figure it out myself. Mechanics are horrible at finding intermittent problems. Checked the fuel rail & fuel injectors the other night based on another post (http://www.jeepforum.com/forum/f13/9...olved-1176480/), but didn't see any blockages there. Pulled the spark plugs, all except cylinder 3 were fine. Cylinder 3 spark plug was a solid mass, see picture. Not sure what happened, but am going to replace it and try cleaning the grounds tonight after work, let you know if it works. Trying to avoid throwing money at various sensors...starting with cheap and free.
well i tried cleaning the grounds. although there was some gunk on the outside of the one on the engine block, there really wasn't too much gunk between the bolt and the lead on any of them. after i took a wire brush to everything i turned it on and just let it idle...didn't want to take it out and get stuck a few blocks over. engine stalled within 20 minutes. restarted it, engine stalled within 5 minutes. the second time when it stalled i had the hood open and though i hard something arc as it went out. sounded like it might have been in the neighborhood of the fuse box behind the battery.
if i coughed up the money for an obii code reader do you think that would catch it when it stalled out? anyone have a suggestion on which one to buy? they are pretty pricey at the local o'riley's auto parts...and you cannot return them after you open the box. doh!
So far I've cleaned the grounds, replaced both oxygen sensors, crankshaft position sensor, fuel pump, spark plugs, distributor cap, rotor & wires, new alternator, new battery, new ECU.... Went on a trip this weekend and its still stalling. Mostly under load when going up hill. Seems like its misfiring, the #3 spark plug looks fouled, but can't figure out why. Will let you know once I get it figured out. Anyone have any more suggestions??
^ agree, but you may want to check the continuity in the #3 plug wire 1st. Or just switch the whole wire with another similar length plug wire and see if the misfire moves.
Did you go with a Mopar crank sensor this time? If not you may be asking for problems. You can check the CKP by undoing the connector and hold the plug/connector to the CKP with the locking tab up. Then take a multimeter set to the lowest ohm setting and put the probes on the middle pin (B) and right pin (C). If it shows any resistance at all the crank sensor is bad (per FSM). Also most often a bad CKP won't throw a code.
I remember ZeeJay saying when he was having real problems climbing any type of grade/hill his ZJ was bogging down really bad with no power. Turned out to be a clogged/bad cat but don't believe it was misfiring. Also we both had vacuum leak problems when replacing the headers. Turned out to be the brake vacuum booster rubber grommet which has a large line to the intake.