Re: Voided Warranty
That is kind of a $#!% deal, and in the US at least, illegal. From what I've gotten about federal warranty regulations, it is expressly forbidden to deny warranty coverage based solely on the use of non-production parts unless those parts can be proven to have caused the defect. That would be the same thing as the dealer voiding your engine warranty because you put a sticker on your rear windshield. The same applies for performance mods. For example: if you get your ecu chipped, it will now cause the turbo to provide more boost than the engine was designed to handle. If this mod causes your piston rings to fry or your turbo bearings to go out, you'd be SOL and the service department would have an easy time telling you to f-off. Whereas, if you get an aftermarket radio headunit and your engine blows up, they cannot deny the warranty claim unless
they can prove that the new headunit or installation somehow caused damage to the engine.
Any time a service department denies coverage under your warranty, be sure to get it all in writing, including the nature of the malfunction, any modifications not installed by the manufacturer or dealer, and the reason they believe it's not covered. You would likely have to get another expert to refute their claim and take it all to court to get relief, but check into everything with the Federal Trade Commission.
This guideline is kinda tough to decipher but still much simpler than the full-text law:
http://www.ftc.gov/bcp/conline/pubs/buspubs/warranty.htm#titling