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WTF?!?, backfire, CEL, doorlocks?

Old Sep 5, 2006 | 02:56 PM
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Default WTF?!?, backfire, CEL, doorlocks?

ok, first, sorry if this is in the wrong forum, i didn't know where else to put it.

ok, so i'm driving to work today, about 3/4 of the way there of a 29 mile trip to work. i'm coasting down a hill on the interstate, somwhere between 55-65mph, can't remember exactly, all of a sudden, the truck has a slight backfire (not real loud), CEL flashes once, and the doors unlock/lock all within a split second?! now this isn't the first time this has happened, but it seems so random, i can't see any cause for it. can somebody please tell me wtf is going on here?

oh, btw, i did happening to be logging at the time, but looking at my scan, i cannot see anything out of the ordinary of why this happened or what caused it.
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Old Sep 5, 2006 | 07:20 PM
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hmmm, my truck has been down (as you know) to have the rear end replaced and once I got it back (took like 2 weeks!) I couldn't get into my vcm via HPT. I actually just sent my box back to Ken@HPT. BUT, I am experiencing the backfires and under WOT I go lean and get HUGE misfires. I also have a bad plug wire that I am aware of, but wouldn't they be all the time?

So to you, I'd say it isn't the tune. SOunds certainly electrical. The CEL definitely is a curve ball. Are you having charging issues? driving around at like 10volts? Sounds as if you aren't pushing the coils with enough volts, hence misfires, not enough voltage to keep key relays locked so your getting CEL issues. I am just throwing some guesses out there. I loose connector on a coil? Have you messed with ANYTHING mechanically in last week?
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Old Sep 5, 2006 | 07:38 PM
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no, nothing mechanically. as best i can remember, this started happening about a month ago after i had uploaded a tune. other than that, i cannot pinpoint anything else. thats the only reason why i thought something in the tune?
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Old Sep 5, 2006 | 07:42 PM
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If the door locks, and other electrical stuff gets screwey, check all your grounds. That's what mine did when I installed my Radix, and had a ground misplaced. Door locks would go up, and down, parking lights would come on, and off. Like it was some kind od voodoo.
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Old Sep 5, 2006 | 07:42 PM
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okay...so it did start happening with a tune. I know you have all your tunes...FULL WRITE the one right before that "bad" one. Well to avoid relearn's, maybe just do a normal upload, but a full wirte might be in order.
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Old Sep 5, 2006 | 07:44 PM
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must be a pittsburgh thing. door locks mysteriously going up and down. all that coal dust is going to your heads.
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Old Sep 5, 2006 | 07:46 PM
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Originally Posted by wkdivr
If the door locks, and other electrical stuff gets screwey, check all your grounds. That's what mine did when I installed my Radix, and had a ground misplaced. Door locks would go up, and down, parking lights would come on, and off. Like it was some kind od voodoo.

haha, you said "voodoo". lol.

yeah, i was thinking that too, but i checked every single ground i could think of. all are TIGHT and solid.
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Old Sep 5, 2006 | 07:47 PM
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Originally Posted by dewmanshu
okay...so it did start happening with a tune. I know you have all your tunes...FULL WRITE the one right before that "bad" one. Well to avoid relearn's, maybe just do a normal upload, but a full wirte might be in order.

yeah, but the thing is, it was so long ago, i can't even remember which tune it started with. and i've done atleast 3 or 4 regular uploads since then.
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Old Sep 5, 2006 | 07:55 PM
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Originally Posted by wkdivr
If the door locks, and other electrical stuff gets screwey, check all your grounds. That's what mine did when I installed my Radix, and had a ground misplaced. Door locks would go up, and down, parking lights would come on, and off. Like it was some kind od voodoo.
Bill- I remember when you had those issues, it is safe to say you we frustrated at the least..

Josh- I dont have a electrical diagram of our trucks but I wonder if there is a main circuit breaker or something that may be going bad? Just a shot in the dark.
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Old Sep 5, 2006 | 08:07 PM
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Originally Posted by 03sierraslt

Josh- I dont have a electrical diagram of our trucks but I wonder if there is a main circuit breaker or something that may be going bad? Just a shot in the dark.
You know...I seem to remember being on the phone with Josh and him asking me if smoke coming from underneath the dash was a good thing. Can ya say hmmm now...
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