Will a computer reflash fix this??

[FullsizeGMC]

A buddy of mine has an 05 2500 Duramax, we were talking last night trying to figure out if when his truck goes in for warranty work he could ask them to re-flash his computer with an updated tune? And if that is possible, would that would take off/reset all of the changes his buddy made a while back with EFI live claiming he knew what he was doing. We were just curious, if when he goes in to the dealer tomorrow, and asks them if they can put on the newest update for his truck (had it done once when it was newer there was an updated tune and they flashed the computer) will that reset what this kid did (as far as ANY parameters he might have messed with, this was a good year and a half ago and neither of us could remember all the $%*t he did to it).

The reason being for this is, my buddy has seen a decrease in mileage from what he used to get before the tune when pulling his camper and/just open road driving. Not saying that the "tuning" he did would have caused this because we arent really sure what he did/didnt do, could be something completely different, but if it isnt than atleast my buddy and i figured he is better off, and can go form there on what he should be getting for mileage!! Thanks for all the help guys!!!

[JustinSilverdo]

His buddy should have his stock tune saved on his computer through EFI live. just download that stock tune back into his truck. The dealer might reject all warranty work for this VIN now. I wouldn't take that truck to the dealer unless it has the stock tune in it. GM has been known to "blackball" any and all mods to Duramaxes. I have heard of people getting turned away for just having hand held tuners...Don't chance it. If your buddy doesn't have your stock tune try the Diesel Place forum those guys will help you out.

[justy]

If the dealership did reflash the computer. All the efi stuff would be gone and back to factory setting. But like above said. He should have the stock tune on his tuner. And also they can terminate your warranty. If they do not like the computer changes.

[FullsizeGMC]

Maybe i forgot to mention but...our OLD buddy did save the stock tune but note how i said "OLD" buddy. We really dont care to hang out with/converse with him at all so....there in which the problem lies. So now we dont have access to EFI live anymore. And we dont want to call him to talk to him, or ask him for anything. Any thing else he can do??

[dozerboy]

I would contact EFI if you don't have access to EFI anymore I think your SOL. Unless you can get a tech to reflash the ECM off the books, but I'm not sure that will work. He may have to buy EFI or find someone who has it or suck it up and go see your old friend. Where are you located in NE maybe I can find someone else around there with EFI.