07 Yukon: Rough Idle

[codythom]

I just bought my wife an 07 Yukon about 3 weeks ago, so it only has 200 miles on it, and we love it. I have noticed a weird thing that has been happening lately though. Every morning when she goes to start it up, you can hear the engine running rough, and feel it as well. I only last about 8 seconds, and then it goes away for the rest of the day. It is only after it has been sitting all night. Any ideas on what it could be? Bad batch of gas, sensor going out, injectors, what? Anyone else have this problem? Thanks in advance!

 

[zipperman19]

I wouldn't worry about it. Mine acts like that too sometimes. Sounds like the gas might be a little bad. Think about it, the gas settles at night and all the contaminants sink to the bottom. As you drive they mix around more and become more diluted. There's a higher concentration of "junk" in the settled morning gas. How old is the gas in the tank? With 200 miles on the car, it might be the old gas that has been in there since the dealer filled it.

 

[codythom]

It sat on the lot for about 1 month with a full tank in it. When we test drove it it had 6 miles on it and a full tank of gas. So now I guess it has been running for almost 2 months now including the times it sat at the dealership on the same tank of gas. I figured that is what it was, but just wanted to check. Thanks for the reply!

 

[zipperman19]

If you still don't need gas, just go fill it up with some 93 octane anyways. It should take care of the idle problems.