My friend has a 2000 trans-am with a custom tune. he had the speedometer
turned off and has been off for a while. my qustion is, the car was missing on one cylinder and i hooked up a gm tech II and did a injector power balance test dropping all the cylinders out one by one we found the problem. but we drove the car right after and the speedometer is back on. what happened? i didn't do any programing

 

How did you turn off the speedometer?

I don't see that as an option on my tech 2

Ryan