Rough engine idle

[Earthworks]

Hey guys. I am new to this forum and have a question that some of you may be able to answer. I have a 2011 Tahoe Z71 and it seems that the engine idles rough. At first I thought it was bad gas so I ran a few tanks but it never changed so I took it to the dealership to see what they recommended and if this was a common problem. They said that it was probably carbon build up in the throttle body so they recommended a flush. No changes after the flush except giving away money. I told them that this didn't solve the problem and then they came back with a memo from Chevrolet stating that rough idle was common in these Vortec engines and this was normal. So my question is do any of you have this issue or have had this issue and found a solution? It just frustrates me when I can see my Tac fluctuate and I can feel the vibration every few seconds when at a stop light or any other time.

 

[ajb1205]

Had the same thing happening in my 2011 Sierra. Ended up being a bad spark plug (I did get e cel light on, though, after a couple weeks of this happening). They also did a flush and now seems to run perfectly. GM doesn't recommend changing plugs until 120,000km...mine only had 50,000km...guess just a bad plug I hope.

 

[Hugh Jorgan]

Had the same problem with my 2011 Yukon. Tech at the dealer said when he plugged it in to the computer, there was an error on the fuel mix ratio or something like that. He adjusted the percentage and it was corrected.