Originally Posted by BlindGoldfish
FYI, I was talking with my dealer about what might void the warranty, and they said anything aftermarket could possibly if it is found to have caused the problem. He gave an example of a 2009 335i with a full exhaust system that threw some code eventually and they couldn't do the warranty work because of it.
It is quite common for a dealer to refuse to do warranty work on a modified car if
the modification may be related
to the problem. There are many members who have been told by their dealer that work cannot be performed on their car unless it is returned to stock. Once returned to stock warranty work can proceed.
(I'm talking about exhausts)
To completely deny/void a warranty claim based on an exhaust flapper, BMW would need to prove that an open exhaust flapper specifically caused
damage. What is more, (assuming you plug it back in when you goto the dealer) they would have to prove that YOU unplugged it and absolutely rule out a bad connection.
Voiding warranty based on tuner codes is a totally different story.