chucktownsend5

I have a 2001 24v. that has a bit of a rough idle problem ONLY when the tranny is in park or neutral( it's an auto.). The idle goes up and down about 25 rpm and the motor sounds a little rough. When the tranny is in drive or any other gear the idle is constant and the motor sounds steady! I took it to the dealer and they said everything was fine, but I don't really trust them! I did a search for "rough idle" and the only things I found associated with rough idle are a dirty/ faulty IAT sensor, a dirty fuel filter or a dirty injector. I'm going to clean and check the IAT and also run a heavy dose of injector cleaner. The fuel filter has bean changed regularly and has allways looked clean. Does anyone have any other sugestions for thing I should check? Thanks.