You seem to be saying that if the ECU has been modified, then VW will automatically deny a powertrain warranty claim. But the dealer has explained to me why that’s not true, and that they have many examples of powertrain warranties replacing major components on tuned cars. In part this is due to the dealership’s supporting info indicating the car wasn’t abused.
I went all the way to the top to get a guarantee on the warranty. Not happening.
No, that wasn't what I was saying.
If your car is tuned and scanned, then the computer at VW will flag it as TD1.
If there is a warranty claim on a flagged car, then VW will determine if the modification caused or contributed to the failure. If so, then the claim is denied.
This is out of the hands of the dealership
Contrary to popular opinion, there are lots of powertrain issues that will be covered, but VW (like most manufacturers) ask one question - is this a failure that is normally only seen on cars with a certain modification? If so, then the claim is denied. If it is a known failure that happens even on non-modified cars (thermostat for example), then the claim is approved.
The problem is that some dealers (especially those that have had chargebacks) will pre-emptively deny a claim blaming it on the mod.
The bottom line, however, is that there are legitimate reasons where a modified car can cause a related failure and those claims should be denied - those are the claims that your dealer should cover.