What make my car to stop.. when driving it just shot...off on 2006 Pontiac Grand Prix

been told to change tranmission +SHIF GEAR 3,4 and it steal does that .. did put on a computer to get a code but every time that the car shots down...it seem that it resest it self so having a big problem to get a diagnostic... very dangerrous on hyway..

3 answers 1 comment
"very dangerous on highway"---depending on priorities--like LIFE---maybe getting it to a local shop(get references) and having it driven and diagnosed first hand might be a good idea.
scan codes and post so we can adv. post eng and trans codes if possible
What did your car shoot the code down? It is dangerrous to steal your shifting. Don't change your transmission yet. Reset itself is a big problem for diagnostic.
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