2008 Starting mystery

[chris jacob]

OK I really need some help on this one. My 2008 Sierra 1500 won't start when it's cold. It turns over once, then all power to the starter is cut, but dash is lit up. The message I get is "engine power reduced." The dealer said the computer lost it's programing, and they re-programed it. Next morning (with new battery) same issue. Later when the temp climbed from 30's to over 55 it started just fine. Any thoughts????

 

[*R1*]

I have heard of issues before inside things like ECMs, Relays, and Switches; that proper contact between two weak points are made or separated by extreme temps. Only way to track down a fault like this, is probably going to be electronic diagnostics with vehicle powered up, but not started, and very cold outside. If the dealers brings it into a warm bay to work on it the fault may not be found. Since they did note that ECM lost its programming, could that fault just appear to be the case on a faulty ECM. They should replace ECM and see if fault comes back.

 

[chris jacob]

Thanks so much for the reply. After things warmed up today it started. So I drove it to the dealership and left it right in the service drive. That way they'll see what a pain it is. I hope they fix it

 

[GMC Customer Service]

chris, let us know how things go for you at your dealer. I hope they're able to get this straightened out for you.

Jeff Morris, GMC Customer Service

 

[chris jacob]

Well yesterday they said that the connection from the fuse block and the ecm was bad, and need a new fuse block. They said it was due to aftermarket wiring in the steering column. The only wire that was tapped into anything there was for a switch for an amp. It had been disconnected for at least two years with no issues. So They installed the new fuse block and $600. later it works. Once in awhile I get an extended cranking, then start with no check engine. Dealer said it's fine. Tonight I had it running in the driveway and I got a check engine light again. Not to happy because I really love this truck.

 

[GMC Customer Service]

I hope this is the last time you have to have your vehicle into your dealer and I hope it's a quick fix for you. Let us know how it goes.

Jeff Morris, GMC Customer Service

 

[chris jacob]

The code was the crankshaft sensor. He said they do go in and out before they totally crash. So even with my 100k warranty it's not covered. Also Do you think I might have a case to get my $ back from GM as they never did prove the aftermarket wire ( that went no where) was the cause of the failure of the fuse panel? He just assumed that's what it was. I also find it odd that they just happened to have that part in stock. Any thoughts?? Thanks