Hi. I have an Envoy 4.2 2005. And it is turning off at idle while waiting at a traffic light or a traffic jam with no apparent reason. Don't give any code and check engine light is off. After turning it on again it can run again fine. There after 3 or more weeks then the problem came again. I turn it on and then runs fine and after three days then the problem came back.. It is not constantly. My ThrottleBody is clean. Its giving me a headache there is no code at the pcm..Thanks