DBS? Consider EMF....
After 15 months of trial and error, and much help from CAC members, I believe my identical problem has been solved. Apparently I had a primary Engine Module Failure....
When I picked up my C6 in January 2005, there were several postings and several theoretically legitimate causes, including failure to put securely into reverse, faulty batteries, power-consuming features that were acting anomolously (poor quality control), cold weather impact, etc.
I tried to isolate my problem and got good help from several of you. I, too, purchased an Optima (from Sears who has the correct parts number) but after the sixth failure, I relented and brought it to the dealer for the third time. The first of two earnest efforts on the part of the dealer dealt with the liklihood that I screwed up with the shutdown process. The second was my first free oil change and a request to check out the reason for the problem. Nothing showed up, and I was then using the Optima.
The dealer requested I call the Chevy Road service line next time it occurred, and I did that three times. The road service is subcontracted, and each time it was at my home in the garage. This time and each more the vette would NOT start. Even with external power, the windows would get stuck in the down position. Weird.
So they put it on a ramp truck three times. I had resisted this in the past as I have little confidence in most of these services. The first time they came very close to ripping off the air dam in front, and secured the vehcile to the bed improperly. The second and third time I had a knowledgeable fellow who understood the nature of the car, and handled it accordingly. My fear of the laws of unintended consequences were well founded, and that was another reason I resisted bringing the vette to the dealer when it had only 3K miles on it. Too many cooks in the stew, all likely performing there own test drives....but after the sixth event, I felt I had no choice. c4c5specialist from CAC commented on my postings, and I finally gave in, convinced he was right: bring the damn thing in....once more.
They had it for a week, and could not isolate the problem. Gave it back to me, and shortly after faced the second flat-bed tow. By now the dealer was convinced that I wasn't making any errors in shutdowns. There was a conversation with the regional chevy engineer. He started at scratch with "do you know the shut-down procedure." Went through it all again. This time the dealer was 100% behind me, and started talking about replacing the vehcile altogether. It was in the shop three weeks. Altogether, in the late winter and sring of 2006, I did not have the vehicile available for about two months.
Then they performed a continous, multi-day (?) check and graphed the ECM at output from zero to 111 milliamps. Clearly the module was faulty, and would act up randomly.
New module: no problem in the past two months. I was fortunate to have a dealer who, when finally convinced it wasn't me ( and their staff was equally frustrated) and that Chevy absolutely had to step in The dealer got some suggestions, and the rest is history. I hope.
I've had three new vettes, C4,C5,C6, and this is the first real problem.
Good luck, and keep us posted. The worst thing is feeling as if you have a problem no one else has. CAC is a network that rivals Chevrolet's understanding of real world operating issues, at least for the first collective million miles we drive. Eventually, there data base catches up and the 'one in a thousand' problems show up, and different solutions are proposed until a final 'best practice' is settled upon.
Yea, I'd buy another in a New York minute.....
philzer
Wierd; frustrating; confusing; maddening!!!
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