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Discussion Starter · #1 ·
My A6 GXP already had a tune when I bought it....want to go back to stock tune (wife's car). Have purchased an HP Tuner and have found (2) stock tune files on their website. Having trouble finding the basic instructions for replacing the current tune on the car with the downloaded tune (and I'm not the most computer proficient person). Also, if the tunes on the website are indeed "stock" tunes, should these be acceptable if I have to take the car to the dealership for engine or tranny warranty work?

Really just want to get the car back to stock and then will prolly sell the tuner as I have no plans to do any mods.

Thanks in advance

Ross
 

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If you bought the car from a dealer then the easier (and cheaper) solution would be to just ask the dealer to flash it back to stock using a Tech II because you weren't expecting a car with aftermarket tune. Or if you can still contact the previous owner from a private sale you could ask if they have it.

Otherwise, I think the best way to do it and use the least number of credits (2 credits for 1 G8) would be to read the current tune and then open one of the stock tunes you downloaded as a compare file against the tune currently in the car. You could then use the HPTuners copy differences feature to copy all your settings over.

I don't think this would be undetectable by the dealer though. Reason being is I had an unlocked tune I created from my stock tune using HPTuners at the track once. I was having an issue, so I decided to let another G8 owner put his Cortex tune in my car. The tune wouldn't transfer from the Cortex handheld until I wrote my 100% stock file back to the car, then it worked fine.

If you only concerned with having the car with stock settings for your wife (and not about the warranty), this method would work fine. You would need to make sure the Calibration VCM OS ID and TCM OS ID's match in the Calibration Details view from HPTuners. Also, to be safe, the controller segments for the ECM and TCM should probably match between your current tune and the stock file you downloaded as well. Someone who is more of an expert about this may be able to confirm for sure if certain OS's and segments are cross compatible, but I can only say that it will be fine if everything matches. Also, if something doesn't match, even though it may work fine, that's another thing the dealer could notice that would tell them you were tuned at some point.

One specific problem I can think of with trying to write one of the downloaded files to your car is you will need to change the VIN # to match, so you'd have to license the downloaded file as well as your car before you could save the downloaded tune with your VIN and write it to your car. Essentially, you'll use double the amount of credits and think of it this way, every credit you use makes the tuning interface worth $50 less when you try to resell it, up to the 8 credits the interface comes with. If you only license 1 G8, then you can expect to only lose about $100ish in value when trying to resell. I say $100ish because the reality is it's worth a little less even since the product is used after all and probably doesn't have warranty for the 2nd owner.
 

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yeah i'd just have the dealer flash it back to stock. but since u bought hptuners already, just get the stock tune from the repository. then read your car's calibration/tune using hptuners, and open the stock tune file for comparison. copy all differences to your calibration, and re-flash your car ("write calibration only" in hptuners).

when flashing your car, make sure ignition set to "on/run", otherwise you'll get TCM errors on the DIC that take a few hours to go away. first time i flashed my car, i made this mistake and bugged out thinking i broke something! lol
 

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Discussion Starter · #4 ·
Thanks guys...I'll give it a shop if I can find the cable that connects to the car.
 

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My A6 GXP already had a tune when I bought it....want to go back to stock tune (wife's car). Have purchased an HP Tuner and have found (2) stock tune files on their website. Having trouble finding the basic instructions for replacing the current tune on the car with the downloaded tune (and I'm not the most computer proficient person). Also, if the tunes on the website are indeed "stock" tunes, should these be acceptable if I have to take the car to the dealership for engine or tranny warranty work?

Really just want to get the car back to stock and then will prolly sell the tuner as I have no plans to do any mods.

Thanks in advance

Ross
Where are you located? I have a stock tune for a GXP that I could send you but you need an unlimited year license for the 2009 G8 to change the VIN# on it. It isn't hard to do but you would have to have 12 credits to do that. If you were nearby I could do it for you but I have no idea where you are.
 
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