Anyone with some knowledge or advice please go ahead and post whatever might help me. I have called every speed shop in the Columbus Ohio area and n one can help. Im hoping my dyno-tuner can get back to me with some more advice. I will start at the beginning. I wasnt paying attention and veered slightly off the road and knocked my mirror off and ruined my radiator core support and AIR pump. The car ran fine after the accident. The car sat for a few months before I got around to fixing it. Then when I went to start it I was getting a few DIC codes. I was getting a low fuel, reduced engine power and traction control error message. The car would crank but not start. It would run if I fed it alot of starting fluid. I also had a buzzing ignition relay at this time. The car had fuel pressure and spark so I figured it was a computer problem at this point. Not sure if its relevant but I installed the LMC5 module for the column lock issue. Anyway, I finally found a shop to look at it and they said the pcm was fried. They installed the new pcm and it ran. I took it to the tuner and it was running great again. Well I enjoyed it for a month or two and then the car sat for a week. I went to fire it up and was horrified to see the same exact messages and issues that I was having. This leads me to believe that its not exactly the PCM, but something else. I should note the wires from the AIR pump are just taped off at this point. Im not sure if that relevant. I dont know if maybe I messed up my grounds when installing the radiator core support or if something else is going on. My tuner said maybe the bcm and said something about checking voltage at the throttle body? I do know how to use a multimeter. The car has a vararam intake, cam and full exhaust by the way. I would REALLY appreciate some help. I love my car and spent alot of money on this issue all ready. I really want to enjoy it for summer but its just sitting and its really bothering me just watching it sit. THANKS!

 

Check ALL grounds and connections, plus look for frayed wires anywhere. These are what cause the most electrical issues.

 

Sounds most like a parasitic draw that is discharging the battery. C5's are very sensitive to battery voltage. At rest (BCM fully asleep, which takes about 15 minutes) there should only be about 30ma draw. The second most likely problem is the electrical connector in the accordion on the drivers door. This connector is known to fail (loose or corroded) on C5's and cause many "weird" symptoms. This is because it disrupts the BCM data. Recommend going to the Corvette forum and searching on parasitic draw, grounds (G Atsma has good advice), and driver door connection. This will give you very good direction to resolve the problem. Pay attention to what Bill Curley has posted on the C5 forum.