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heehawbus 08-30-2010 11:18 PM

Bad PCM? help!
Hey all, been having a weird issue later that the dealer cant replicate or diagnose:

Last monday i was driving everything was normal, stopped at a light and truck just died. would not restart but was cranking like normal, got it pushed to the side of the road, still wouldnt start but would crank just fine. No codes came up and eventually it wouldnt even say done it just went to mileage. So i got it towed to the place that always fixes it and they said nothing wrong with the fuel pump (which is what i thought it was) and no codes and all the found was the battery was shorted (3 years old in NV, time to replace) so i have that replaced and picked it up. The next day i was driving and it stalled out again, this time while i was moving, but right before it stalled out it felt like it was down on power and then died out. so i tried to resart it again, same thing, cranked just fine but no start, let it sit for a couple minutes and it fired up like normal. So then i let it sit for an hour checked the codes, nothing, started it up and drove back to the shop, stalled once at a light on the way back, but started right back up and made it the whole way.

So the shop i took it too said this time they let it run and it died out and they determined the pcm was bad and needed replace, but they couldnt do it because they dont have the equipment to reprogram the key :puzzled:

so i take it to the dealer and they had it all weekend and just called, they said they could NOT get it to replicate any of the issues i decribed to them (the stalling, and this weird shifting issue where it feels like it stays locked in gear when you let off the gas). he said they drove 13 miles and nothing and had to come back cause gas was low, so they are going to get more gas and try again, but he said their equipment says theres nothing wrong with it and it drives perfectly (even thought it still feels down on power not as much as before but still some) and says that the pcm might be an issue but cant say for sure because it didnt happen for them.

anyone have anything similar happen or have any ideas? i would really like to have my truck back (running and reliable) its been a damn week :(

also some more info as i missed but others have mentioned on here. when it died the first time and i tried to restart the only lights that came up on the gauges were the low gas light (had a half tank) and the check gauges light were on, and the sentry key light, no mil or anything, and the same thing happened the second time it died while moving. i was trying to search on here for other people with similar issues and some one mentioned that they had the same lights on but there was no replies or resolutions.

another thing that happened when it died all 3 times were the gauges wouldnt show right away that i lost engine power or anything was wrong, after about 3 seconds though it would show engine speed at 0 rpm just like it normally would when it stalls, dealer guy says that it should happen like that they should all just drop and keeps bringing up the cluster might be bad but the cluster isnt causing it to stall..

any insight please would be so much appreciated

Escape 08-31-2010 02:35 AM

Re: Bad PCM? help!
Crank position sensor?

Scottina06 08-31-2010 03:15 AM

Re: Bad PCM? help!
odd that there are no codes........almost sounds pCM like

heehawbus 08-31-2010 05:53 AM

Re: Bad PCM? help!
some one on ju mentioned the cps but that seems like it would only make sense if it was just dying and starting right back up,

also lately its been doing some weird things off and on, like when i take it to town square i alwyas park in this certain spot at the end of the lot, and twice now, when i get out and go to lock it i can hear the lift gate click but no lock and honk, no matter how many time i hit lock (on the key) so i have to lock manually, if i put the key in the ignition and power on it honks and then if i shut it off it locks normally, its done this twice so i figured it was some electrical signal messing with it (near the airport) but then it did it again last week at the gym.. every other time i lock it its normal..

and then when i was driving home on the highway, going about 70, 5 miles till empty it just sorta cut out for a second, gauges went down, cruise went off and it beeped and said 0 miles, went to go get gas really quick and noticed one of my HIDs was off (driver side) shut off the lights, waited and turned them back on, fired up no prob, truck ran fine (except that weird shift thing)

i hope everything is because of ONE thing and they can find it because its to the point now its unreliable and i cant have that.. just hate leaving my poor baby at the dealer for them to do god knows what to it..

Scottina06 08-31-2010 07:05 AM

Re: Bad PCM? help!
it def. sounds electrical...could be as simple as a ground......or as expensive as a PCM

DJ BoNiOmArIo 08-31-2010 09:17 AM

Re: Bad PCM? help!
well if it is ur PCM ur in luck cuz I have one laying around but it sounds like it's electrical I had a mountain of those issues and all I did was buy $5 electrical contact cleaner, disconnect all sockets going into PCM and also the harness behind the fuse box on the drivers side, spray them really well and let that dry over night ... then all the problems were gone interesting I know and funny part is I found that out after dropping $2K in fixing other crap that didn't need to be fixed which included a new PCM when I put my old one back on it works like a charm so it wasn't a PCM issue

lewi3069 08-31-2010 11:30 AM

Re: Bad PCM? help!
On my old WJ my CPS went bad and I could crank it all day but it wouldnt start untill about 15 to 20 min after it died.

Asativa 08-31-2010 12:50 PM

Re: Bad PCM? help!
crank position sensor, or pick up coil in distributor. see em all day long. both relatively easy to replace urself and for cheap. so either diy with my guess, or take it to a shop when its actually acting up for them to figure it out. andy

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