Joined: Sep 2012
Location: Fluvanna County
A good dealer will not blame EVERY engine issue on an aftermarket tune. There are plenty of cases of guys with tuned cars receiving powertrain warranty services.
On the other hand, there are also cases where dealers tried to deny coverage for axle-back exhaust and shifters.
A lot of it comes down to the dealer, at least initially.
So, I wouldn't say that a tune "automatically" makes your warranty go away for ANYTHING. Yes, I read the TSB. There are certain types of failures that seem to get pinned on tunes. Not every failure.
In a nutshell - you run SOME risk if you modify ANYTHING on your car IMO. Personally, I chose to make my car what I want it to be now rather than wait 4-5 years to hit 60,000 miles (this is a DD).
But if you really can't afford any car repair bill, don't mod. Just in case.
Also keep in mind that plenty of dealers seem to be not fixing things by simply saying it's "normal" whether you've modded or not. So we can question how great the warranty is to begin with.