Ok everyone, here's all the info I can muster. Any input is greatly appreciated

Vehicle:
2000 Camaro SS
6 speed
~6X,XXX miles

Car sat for about 3 years dead, 98% of the time with a dead battery as well. Ran fine as far as the computer goes before the motor went. It would give me some trouble connecting with my laptop/HP Tuner suite when it was running, but a friend could connect his with no issues. I remember us discussing it possibly being some issue with my setup, but can't remember details - this was back in late 2008/early 2009.

Car is finally back together, new battery in. Dash lights up, but weird issue #1 is that the fuel pump was not getting power. Chalked it up to some wiring with the nitrous system previously in the car messing it up, and just jumped it running a wire from under the hood to the relay as a temporary work around to empty the tank. Not sure if that was the real problem now. Issue #2, at a separate shop to get tuned, and they can't connect to the computer, AT ALL. No HP Tuners, not even a plain OBDII scanner. Knocking, but nobody is home.

Turn the key to run and the dash lights up, mileage comes up, usual warning lights come on, headlights work, door locks and windows work... But the computer is AWOL. To the best of my knowledge the computer wasn't touched at all in the taking apart or the reassembly or any time in between. Also as far as I know all grounds are connected, but could a lone ground left unnoticed somewhere be causing all of this if everything else still works? Connections on the plugs all look to be good at tight, PCM shouldn't have gotten wet, only welding done on the car was tacking a muffler onto the exhaust pipe, don't believe any welding was done on the body.

Can anyone offer any advice, anything we might be overlooking... Old tune/tuner locked the PCM maybe? Or is it possible that my computer just went brain-dead from 3 years of inactivity?

Thanks in advance.



EDIT: No, we have not tried starting it to see if the computer is still alive, because the new motor is a vastly different setup in every way from the old motor, and don't want to risk it. The shop is running into these errors attempting to put a preliminary startup tune in the car.

 

The basics...check fuses, etc. The com port IS fused, so might be the issue. Other than that....yes, grounds can play hell on a car that sits for a couple of years. I had MANY ground-related issues on my Fbody after it sat for a few years (indoors), so that's a distinct possibility. My advice; unbolt and clean EVERY ground point that you can find....especially the one on the back of the cylinder head. Also unbolt and clean the grounds by the driver and passenger kick panels. A wiring schematic is your friend here...

Good luck. Hope it goes quickly for ya.

 

Ask somebody from the tuning shop to check your PCM.
They must be able to test your PCM into another car or on a bench harness, to see if the PCM is really bad or the car has a wiring problem.

Also, a PCM from another 99-02 Camaro should crank (won't start), but the fuel pump and starter will work.

 

Bump.

Appreciate the feedback so far; any other words of wisdom?

 

What have you done so far? The above suggestions should have just about covered it, but what results have you had?

 

Haven't had a chance to run by the shop and look it over with them yet. Just trying to get as many suggestions as possible to try out, incase it's not a simple issue to resolve.

 

mine did the same thing it was the ground from the block to the frame on left side front

 

Left from the front or back of the car (driver or passenger side)? I remember there being a ground strap on one side of the block, but not sure about the other.

 

driver side front behind alternator runs to frame rail below fuse panel