What issues for idling do you have? Does it stumble once in a great while when the engine is not up to temp? I get an idle stumble once in a while, but that is normal. My old Saturn aura had the 3.6L (non DI) in it and it did that as well. My 3.6 in my ATS idles 10 times smoother than the 3.0T engine in an audi s4 a guy I work with has.