So I recently took my 2019 Special Edition Golf R to my service center to have the water pump/thermostat replaced as my usual mechanic found a leak and suggested I took it back to a VW service center to fix under warranty.

After inspecting my car, the service center called and asked me if my car has been modified or tuned at all, because if it has I will lose any type of tune that has been done when they replace the water pump/thermostat. I said I don't think so since I'm the second owner of the vehicle and there was no paperwork about a tune included when I bought the car from the dealership.

Since I've gotten the car back, it sounds a bit quieter, and I don't hear as much crackles and pops from it...well I think so anyways so then I thought maybe my car had been modified in the past.

So is this even a thing? Does replacing the water pump/thermostat revert things back to stock settings? Or has my servicing center done something dodgey?