Originally Posted by textallguy
I've got the same thing on my 03 Envoy XL with all original equipment and only 89k miles on it. I happened to replace the battery a few months ago and the problem went away for a few weeks, then came back same as before. I wonder if it's a sensor problem...
I haven't tracked it down yet, but I think I've narrowed it to the idle air. It seems to start find when cold, but when warm I'm thinking it could be getting a false reading from a sensor as well...maybe the intake air temp sensor??? I don't have a shop manual yet, so I'm not entirely sure how it uses the reading from that sensor.
Something seems to basically flood the engine when it is warm. Once I hold the throttle body open just a little it starts up and after a short stumble it takes off and idles find.
Haven't had much time to trouble shoot just yet...but I will find it. Let me know if you guys have any ideas!
Come on moderators...where are you..lol. What is the test procedure for the intake air temperature sensor...what are the readings I should get across it with a meter?