Does anyone have any suggestions on what to check on an 07 Suburban that has a rough idle right after starting. It definitely goes away, but I don't remember it doing that 20,000 miles ago. I thought it might be as simple as plugs, but thought I'd throw it out there first for the experts! Vehicle has around 55,000 mi.

Thanks

 

I had a rough idle on my 07 with about 42K miles on it at teh time.......(15K of those were supercharged, since took it off) I tried plugs/wires thinking the same thing, didn't help if anything made it worse...brought it to the dealer and my cats were fried. I've heard of this happening on quite a few late model GM vehicles (04 gto, 03 avalanche, vettes etc.)

 

My rough idle was caused by a plug wire that had come off. Weird as I had never touched them.