Not really. Its an aftermarket part. Your dealer has every right to refuse work on your vehicle if they can prove in writing that the modification you made was the direct cause of your warranty claim.
if you choose to modify your car, and If it turns out that your modifications are the cause of the problem, the dealer has every right not only to charge you for the diagnosis and repair, but to also void the portion of the warranty that has been compromised by the use of those aftermarket parts. Likewise, a dealer may refuse to service your car if it is adorned with aftermarket parts to the extent that its technicians cannot reasonably be expected to diagnose what is wrong with your car.
I'm not trying to scare anyone away from getting an exhaust. I'm putting on Corsa soon. What I am telling you is that dealerships can, if need be, void certain aspects of your warranty, if they can prove that the direct cause of your warranty claim is the sole responsibility of your modification.
"Never say "never".
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