Should I flash stock tune before going to dealer?

[fiiiesta]

Also, would my Cai or cat back cause any issues with power train warranty? Think I need a new axle.

 

[XR650R]

Depends on the dealer. I doubt the CAI or exhaust would be an issue, but the tune might. I'd go ahead and flash it back to stock.

 

[Capri to ST]

One thing to keep in mind is that dealers have access to a counter in the ECU, which will tell how many times the car has been started since the ECU was flashed. If they checked this, it can tell them that a tune has recently been removed, since removing a tune typically reflashes the ECU.