No I have no problems with my warranty, they are covering everything. someone else had a similar problem and the dealer the car was towed to are guessing at what the problem is and trying to deny the warranty. Koons knew what mine was Monday morning after I drove it in Saturday afternoon with reduced power,they called GM Tech, just haven't been able to get the new fuel rail, fuel pump has been in for a week. Koons has been awesome to me, no problems at all. (Joe do you really think these guys would want to mess with me, easier to fix the car and make me go away

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They just called my car is done, they put the factory tune back in it, GM Tech said they had to, but no issues on fixing the problem. The only charge is for replacing a brake light bulb that was out. I have NEVER used Mobil 1 in my car, first oil change was to Castrol Syn. (found out they weren't 100% synthetic either) then Royal Purple ever since. I asked the service writer about the oil issue, he told me than can ask for receipts to prove you changed the oil regularly if you did it yourself but it DOES NOT have to be Mobil 1, it just has to meet GM Spec. If you don't have the receipts you can have the oil analyzed to prove it is still good, and they can pull the filter and have it checked. If it is an oil related problem. GM Tech was told it didn't have the stock tune, they said unless the engine is blown just fix it, that was from GM Tech direct, NOT the dealer. They also bled the clutch as they said it didn't feel right, and there is a TB out with a new bleed procedure to improve feel.
Lesson learned reset tune to stock before going to dealer, I limped in from way the heck out in MD and just forgot, I was trying to drop it off before they closed.