General Maintenance & Repairs - Bad Bcm?




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robTA
09-24-2008, 07:50 AM
i have a 01 trans am. i came home from vacation and tried to start it but it wouldnt start. it cranks but nothin else. there is no spark or fuel. everything else seems to work fine, but the gages dont. and my friend tried to scan the computer but it said it was unable to communicate. he thinks its the body control module. he removed it and it was kinda hot. we didnt take the bcm apart yet, but does anyone know if this is right? or is there another problem we should check? we already checked all the fues and relays. and while i was on vacation it did rain a lot here. while no water actually got in the car it was very humid and i think moisture may have gotten in the car. any help would be appreciated.


Weezzer
09-24-2008, 11:07 AM
Do you hear the fuel pump prime? Could be the pump or the fuse, also check the ignition fuse, see if it's good.

2002_Z28_Six_Speed
09-24-2008, 11:11 AM
The engine would start and run for a second then cut off if it was the BCM security. Sounds like an overall electrical problem or PCM issue. You should check out to see if the PCM has power on all of its power wires. Make sure all your fuses are good.


2001NBMZ28
09-24-2008, 11:54 AM
Double check the GAUGES fuse inside the car. BCM and instrument cluster are on that circuit.

robTA
09-24-2008, 02:13 PM
thanks, we did check the fuses and when we scanned it it said unable to communicate. if its the computer is that expensive? i know ill need to have it dyno tuned again

2001NBMZ28
09-24-2008, 02:45 PM
Don't know if this will help but the PCM is covered under the federal emissions warranty for 8 years/80K. Did your tuner keep the dyno tune, maybe they can try to reflash it?

robTA
09-24-2008, 03:13 PM
my car has 93000 miles. but i just called the shop and he said if it is the computer theyll prob just dyno tune it again. and he said the comp is about 250$ the dyno tune prob wont be 2 expensive . so if thats the case it still wont cost that much more than the fuel pump, which is what we thought it was at first. it kinda sounds like thats whats gonna happen. its not a huge deal i have another car i barely drive the ta anymore. but thanks for the help. and ill let u know what happens.

2002_Z28_Six_Speed
09-24-2008, 03:22 PM
I'd rather get a PCM off ebay or a sponsor here. You would be looking more around 50-60 dollars that way.

robTA
09-24-2008, 03:32 PM
would that be for a new one or a used one? id rather get a new one

2002_Z28_Six_Speed
09-24-2008, 03:36 PM
Used. I don't see an advantage to a new one unless the previous owner flashed it 100 000 times.

robTA
09-24-2008, 03:52 PM
ok so its ok to buy a used one? it didnt rain a lot here last weekmy car didnt take any water but do u think the comp went cuz moisture?

robTA
09-24-2008, 05:20 PM
my friends thats workin on my car just called me. he said he and the guys at his work think its something wrong w the ignition. he said he wants to take the steering wheel off cuz it might be the tumbler. i told him that doesnt sound right to me. what do u think? even if somethnig was wrong w the tumbler the comp would still work right?

2002_Z28_Six_Speed
09-24-2008, 08:06 PM
You would know if it was a lock tumbler because it wouldn't rotate.

Bad ign switch? Not likely. You wouldn't see the gauges come on and it wouldn't turn over.

If you can hear the car chiming and everything else is coming on I would look to see if the PCM is getting power.

Can you hear the IAC motor moving when you turn on the car?

robTA
09-25-2008, 09:24 AM
im not sure if i hear anything turn on when i turn the key.. but the gages dont work they kinda flicker but theyre not on

robTA
09-25-2008, 04:48 PM
my buddy the mechanic just called me, he took a look at the computer and said it definitely looks like it was damaged from water. he said the outside is coroded. i live in chicago and a week and a half ago there was a lot of rain and my car was sitting outside, i couldnt move it cuz i was in california.i think its because i have an aftermarket ram air hood. it fit pretty good, but i bet thats what let so much water hit the comp. does taht make sense to u? so hes callin the dealer to get a price ill be able to get it at a discount, but ill have to take the car back to speed inc for a retune..