cpatrick

I've gotten soo much help here in the forums. I can't think of anything i've done to my rig that hasn't already been posted, here or in other threads. ...so not sure of what to contribute to others out there. But Thank you all for then, and in advance for now.

I've read allover re: pcm issues. I'm about to replace mine and thought I'd mention the symptoms.

96 xj, 229k, 4.5 la, sye, ext ds, borla hdrs, magna flow exh, etc
replaced overall: tps, cps, iac, plugs, wires, cap, router, ign coil, fuel pump, o2 u/d stream, clean throttle b, seafoamed, new 4 hole injectors, alternator, batt, starter, ...all checked out fine. done several more r/r's through time.

so recently it started stalling - like a hiccup in fuel. brief choke type stalls. on the hwy, and between lights, etc. intermittently. finally within a weeks time, it occurred more often. never died, fully stalled, nor any codes. it seem like if i let off the gas a bit regained flow, but really hard to tell. so finally late morning, drove about 6 miles, stopped got back in ...fully died in drive 35mph, came to a stop, cranked back up, dies two feet of movement, wouldn't restart. sat for an hour, restarted and done nothing but sit - test drove up and down the street, pushin it kinda, stopped thought i'd drive it on main roads - then it instantly died again. this time no restart. cranks strong, lights and all working fine. (no gauges btw) but batt and alt are good. i heard my fuel pump motor, so started thinking cps (oriellys), pulled and replaced, nothing changed. noticed fuel pump no longer running at turn of key, checked fuel rail - zero pressure at release valve. ignition coil is new, other sensors as well, ....EXCEPT - i dont think i ever replaced the cam sensor (pickup) at distributor. got a mechanic checking it out, we noticed random/erratic clicks coming from relays, starts up and dies just as quick, dash lights flickering, engine light, and neighboring lights flickering, obd he plugged in claimed connections made, connections lost within seconds, it too was going off and on erratically. so kinda thinking pcm.
saw prices folks posting out there, im in houston - i found a dealership pricing it at 312.00 with core exchange - 125.00. he's getting back to me re: rebuilt or refurbished. the warranty is only two year. the only lifetime i found is fs1 online - and read poor reviews. but it was much cheaper.

dk if i left anything out - heard of folks replacing pcm and no luck. few - but some. i moved it around wiggling it - no luck of noticing anything as it wont stay running long. zip tie - hadn't done that either, cleaning and checking prongs, nope. so 'ill probably tinker with those. oh, and a lot of flooding rain here lately, but no high waters messing with me. i unplugged and replugged the 3 lg connectors at pcm, all seemed clean, dry and well in tack.
I love this jeep - and am determined. what can i say!

anyways: any reason why i shouldnt replace the pcm at this point?

again, im new here - not sure how ill get your replies, hope i placed this in the right catagory. Thanks all

Jeep Driver

Pull one from a junk yard and try it, doubt it's your problem, however.

Guarantee you it is a connection problem, ground, cables, other.......


'96 is a bastard year, make certain you get the correct PCM.


And, here- http://www.skillsyouneed.com/write/punctuation1.html

Ralph77

You know what I don't think I saw in that list is the temp sensor. The one in the thermostat housing. Don't know if this applies but I am going to throw it out there. Have a buddy. Owned a '96 4.0. She was running like crap. He figured tune up. Plugs, wires, cap, rotor, and new fuel filter. Still ran like crap. Drove him nuts till he figured out it was the temp sensor.

cpatrick

Thanks for the .02 JD. I didn't think I'd find myself on the hunt for a working cps. Turns out several years ago, in similar, but not so drastic of symptoms, I replaced the cps amongst other things and kept it in a tool bag.
After 4 cps swaps from oriellys, this time around, I ordered oem from a dealership last Friday. It wouldn't be in til the following Tue. So I stumbled upon the old cps, installed, and fired right up. (Donkey). I'm guessing back then, it was never the culprit.

I'm still purchasing the oem - as I believe the current is the original. Besides, its only been two days of mild driving.

Now all sensor, and relay replacements are going to be oem Period.

Thanks for the reply. And as to the link... Lol, working on that too.

cpatrick

Hey there Ralph77, don't think I've ever addressed the temp sensor. I've owned this jeep for about six years. It had 150k at the time. Grandma owned.

I'll keep it mind. As we all want our rigs tiptop, It was laughed upon another post "...And you bought a jeep".

I'm learning general maintenance. I don't enjoy waiting for something to fail, but don't want to spend unnecessarily either. Not broke, don't fix ...to some degree huh.
So far the cps is the suspect as it seems. (As I recently posted) I'm gonna have to get meters and learn the proper testing techniques of sensors, relays, and overall electrical troubleshooting.

Thanks for replying.

Ralph77

Check out CJ7-Tim's post here:

http://www.jeepforum.com/forum/f11/c...-maybe-889010/

Also look for posts by cruiser54 and CCKen. All these guys are around this forum and others. I want to say they have also posted about the CPS but can't find them. I know they have offered useful advice and I have learned stuff about problems I don't have and hope I never will.

Utah1970

I had the same exact problem driving my 98'. The prior owner replaced the CPS and Fuel pump thinking that would solve the issue but it just put off what would needed to happen from the beginning.

The remaned computer came out of Florida and I believe it cost me around $350, if you need the info please let me know.