Hello
This is my first post as i am new to this world and i hope i am posting in the right place.
My problem is when trying to write the tune to the car it stops and a says timmed out and car cant even start after that,
Then i pulled out the ecu and try to write it on a bench wiring and its fine.
So WHY CANT I WRITE AS THE ECU ON THE CAR AND CAN WRITE THE SAME ECU ON BENCH WIRING?
2003 GMC Sierrra
MPVI 2