I my envoy will go into engine power down mode while I am driving.

What is your question?

It's been taken to 3 gm dealers and each time they do something they say they have fixed it. This last time the dealership said they could not duplicate the problem so I should bring it back when it does it again, the funny thing is that I took it in there doing. If you turn the car off long enough it will and restart sometimes its okay other times it start in engine down mode. The diagnostic code is P2138 and they have replaced the throttle body but it continue to do it. It started the first time 11-22-14, at that time the dealership said I had 6 broken wires and they repaired those wires, then 12-11-14 it did again and the dealership said it was a bad throttle body. On 1-6-15 it happened again and the dealership cannot duplicate the problem and doesn't want me to waste my money replacing thing so they suggest I pick it and bring back in when it does it again. Each It has been taken in in engine power down mode. I feel that I am getting treated poorly by these dealers and all the dealers have been different because when it happens I take it to the nearest Gm dealer.