I have a 2007 Denali 6.2 While driving highway speed the Service Stabilitrak / Service Traction Control Warning light will come on and remain on for a 5 to 10 miles and then it will go off. I have taken it to my GM dealer 4 times (the last time the light was still on) there were no codes that fixed the problem. Bleow is what they have tried.


The first time they replaces some of the wheel sensors.

The second time they cleaned the throttle body and after they were done the vehicle would not start so I was told the computer needed a program upgrade. After that my gas mileage went from 18.9 highway to 16.7 and I drive a lot of highway so i'm not happy.

The third time they could not find anything wrong

The forth time, Last week they told me the cam sensor was bad (big $$$$ to change on a 6.2) the next day the warning is back on.

Things I was told to try on my own: I have tried fuel additives, change the gas station I buy fuel from. Try using a lower octane fuel 89 octane (I like to use 90+ octane) Try Using Fuel with out alcohol, I have Changed the plugs and wires.

I have spent over $2,500.00 trying to fix the problem with no luck.

When I spoke to the GM dealer a few days ago the only thing they told me was "clearly the things we replaced needed to be replaced. We just have not found out what is setting off the warning light." My coment back was Clearly you have no idea what is wrong.


What do you think is setting off this warning light?

 

I know that this won't help much but your not alone. I am in the same money pit as you are friend.
Studied it a bit, and noticed when the mailed invitations for a trade-in or upgrade for vehicles stopped coming in. That's when I should have begin to pull the trigger on trade-in or upgrade so it would have been the dealers or someone else's problem. Though a dealership salesperson will obviously beat us up on the front end and back end of a trade-in or upgrade. I know well now. Sometimes I's get away, sometimes I's get hooked. This time I got away and got took.

 

Did they actually replace the throttle body? I did and it fixed mine w/same issue. 5.3L.

https://chevroletforum.com/forum/tah...ur-home-88271/

https://www.thecarconnection.com/new...rough-v-8-idle

 

I just learned about this on a used Suburban I bought. A good thing for me is that I just decided a few months ago to buy a Snap ON Solus Edge scanner off of Ebay. What happens on the 5.3 engine is it has a system to kick down to 4 cylinders. This involved taking oil pressure away from certain lifters. 1, 4, 6 and 7. You need to get a good scanner and check the history of the misfires, easily done with the Solus Edge scanner. Mine had over 38,000 misfires on cylinder 4. Once reading that I changed the coil pack, spark plug wire and spark plug just to see the difference. Nothing changed. On this particular scanner you can turn to live feed and watch your engine while it runs for misfires. Mine kept it up running my misfire total up some more. What happens to the computer when it detects all these random misses is it shuts down the Stabilitrak and Traction Control giving you that nice error including the check engine light on your instrument cluster. No misses, no errors. You have misses you should eventually get the 0300 error code. There's a service bulletin out on this. 80-06-01-018B. They don't talk about the misses but I have a really tech savvy mechanic friend who knows all this by heart. Good luck..