If I install a cold air intake on my mini s, would that void out the warranty I have with them?

 

Simple bolt-ons like that won't void the warranty automatically. Basically, to deny warranty coverage for a defect, the dealer is supposed to show that the defect was a direct result of the modifications you made. That's not how it always works, but that's how it's supposed to work.

So, if you put on a cold-air intake, and you later make a warranty claim because your headlights stop working, you probably won't have a problem getting the lights fixed under warranty. But if you start having engine problems, they may give you some resistance fixing it under warranty if there's any chance at all that your intake could have had anything to do with the problem, even tangentially.