thast what I was thinking... is there anywhat that they could vag it or something to find out recent performance?

 

Everytime somebody has asked a question about warranty I give them this info.

Legally, a vehicle manufacturer cannot void the warranty on a vehicle due to an aftermarket part unless they can prove that the aftermarket part caused or contributed to the failure in the vehicle (per the Magnuson Moss Warranty Act (15 U.S.C. 2302(C)) . For best results, consider working with performance-oriented dealerships with a proven history of working with customers.

and here are some more info
http://www.rosenentertainment.com/Ma...Air%20Acts.pdf

Hope this helps.

 

When a CEL light comes on the ecu take a snapshot of the current conditions of the motor, so yes depending on the performance part. Say if you had an aftermarket turbo boost levels would show higher the factory spec but something like a cold air intake wouldn't be noticable to the diag equipmentunless visable, but a MAF with oil on it and a CEL for a bad MAF sensor would be obvious and will still void the warranty.... at least it did at the dealership I work at.