PCM problem.
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From: Bossier City, Louisiana
That should not effect the reset procedure. I've done this to myself accidentally quite a few times and I've never blitzed a PCM or damaged it. I should be more careful and maybe I've been lucky. But what I have noticed is my LS-equipped El Camino is much tougher to initially start when I do this because the PCM has to re-learn a lot of things. It also runs a little rough for the first 30-45 seconds but after that and a warm up cycle to normal operating temperatures, its back to dependable operation.
I never recommend the use of starting fluid / ether as a crutch to chronically get a motor running - it washes oil from the cylinder walls. But it is useful as a diagnostic tool once or twice. Spray some "explosion in a can" starting fluid ether past a fully opened throttle and attempt to start the engine.
Rick
I never recommend the use of starting fluid / ether as a crutch to chronically get a motor running - it washes oil from the cylinder walls. But it is useful as a diagnostic tool once or twice. Spray some "explosion in a can" starting fluid ether past a fully opened throttle and attempt to start the engine.
Rick
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Pcm I’ll give that a go. Btw here’s the story: I drive the car roughly once a week sat Sunday morning type of thing. Start the car up crank up the sounds ac etc take of cruising and everything starts acting up. Amps cutting in and out ac cutting on and off etc turn off everything and head home thinking time for a batt. Batt aprox 2 years old so I figure prob solved. Car starts runs like normal again come back home and just for ***** and giggles I put a meter to the batt and it’s pinned at 12.2 volts. I think pretty much everyone knows that means the alt is not charging so it’s early enough to swap out an alt no big deal. Get that done and have the same prob so now it’s trouble shooting time. Figure I’d start with that dumb *** exited wire. The plan was to back prob the wire at the terminal 15 but I screwed up when prying the plastic cover off and yanked the entire plug from the PCM and now I have nothing but crank.
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Joined: Dec 2017
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From: Bossier City, Louisiana
Do you get any power at the OBD II connector with a reader plugged in? I'm thinking broken power wire into the PCM and I have 4-5 different power inputs on mine and probably four grounds.
Rick
Rick
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Pcm Yessir reader hooks up fine pulls codes etc. I’ve been working so much OT I really haven’t dug into deep prob an hour here hour there and then decided to chime in this form to pick some brains. Thanks for the tips btw imma spray some ether see if I can eliminate spark from the equation
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I disconnect all kinds of PCMs without pulling the battery cables and never have this issue. and I do a lot of J2534 programming and diagnostic work.
I believe your issue is you cleared a failsafe in the older gm cars that when it lost the key signal from the little chip in the key that it stopped looking for it. ill get calls all the time never had a problem cranking it till the battery died. since the vehicle isn't running and it never receives the key resistance then it goes into security mode. if so go to your local car audio store ask them if the have a gm vats specific pack of resistors and solder it in place of the security wires.
I believe your issue is you cleared a failsafe in the older gm cars that when it lost the key signal from the little chip in the key that it stopped looking for it. ill get calls all the time never had a problem cranking it till the battery died. since the vehicle isn't running and it never receives the key resistance then it goes into security mode. if so go to your local car audio store ask them if the have a gm vats specific pack of resistors and solder it in place of the security wires.
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From: The dirty taint of the country. ...Los Angeles
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iTrader: (3)
Joined: Feb 2006
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From: The dirty taint of the country. ...Los Angeles
OPTION 1 ... Under the dash VATS bypass. I had this in my car for 8 years.. Then it started having the issues again. 8 years though, not bad. I made these first 2 vids since NO ONE had ANY video tutorials at the time ..in the hopes that would help out others.
1.) PREP
2.) END RESULT
OPTION 2 ...VATS Passkey 10 minute reset procedure .... This will work if you're stuck somewhere and you just need to get it going. BUT It'll come back on the next time you try starting the car so... don't stop for fuel on your way home after doing this. Ask me how I know. I did the bypass under my dash after needing to do this a handful of times.
OPTION 3 ... And by far the BEST option, tune it out. I used HP Tuners since I have an MPVI2 now. Make sure that you do a "Write Entire" because if you do a "Write Calibration", I'll just come back. But your buddy will need to license your pcm to get in there and do it so it's gonna cost $100 for the 2 credits to do it.
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Pcm This guy says he can relearn the key back to normal but I’d rather delete them entirely if I can. $180 for him to show up so we’ll see. Then I still have the charging issue to deal with I think that’s the exiter wire but I can’t even touch that problem until I get the car running again