Originally Posted by strobe89
I have a 2008 328xi I purchased a few months ago and interested in the AA tune. Using the simon tool, could I remove the tune and go back to stock for warranty work? I have a CPO warranty for about 2 years left still and was hoping if I got the simon tool I could switch tunes before going into a dealer. Any chance the dealer would be able to find out even after reverting back to stock tune?
Once you have the tool, you should be able to switch from OEM to AA tune whenever you want. Keep in mind the process can take around 45 minutes....longer or shorter than that depending on your model year. So it's not something you'll want to do all the time.
It's also recommended you have a battery charger hooked up at the time. I'd guess that bad things can happen if the battery goes dead during the process. So, get a battery charger too and make sure you turn off as many accessories as possible during a program.
I bought a Simon primarily as insurance against a dealer overwriting the tune. I can't imagine dealers check that for most warranty issues. It's also insurance in case I or someone else accidently put 87 octane in the tank.
One other nice thing is that you can revert to OEM prior to selling the car if that person isn't an enthusiast.
One other thing to note is that once you use the device, it'll be locked to your VIN. So it can't be used on any other car.