I have a 06 Grand Touring, I sent my car to Z1motorsports for a new Osirus tune and when I got my car back my analog and digital speedo no longer work. On top of that my mileage counter isn't counting up my miles as I drive. Any help would be greatly appreciated...

 

It was not working from the moment you received the vehicle? Id see Z1motorsports about that.

 

They said it was most likely the ABS Speed Sensor when I questioned them on it, and that it had probally go out when the car was on the dyno. Being I am 400 miles away I didnt argue with them on it cause I was ready to get my car and make the drive back home...

 

The Z has 4 wheel speed sensors. The loss of one would cause VDC/TCS issues and throw a code. The loss of all four isn't very likely so you shouldn't lose odometer/speedometer functionality. There's never been any evidence to suggest that only one wheel speed sensor provides the speed/distance information so I don't see why they would say that was the cause.