My 02 stroker has what sounds to me like a cross between a rattle or a groan. (hard to explain) I thought it might be kinda like some ice laying somewhere. It only does it when idling and when you touch the gas ever so slightly its gone. There is no real pattern to the sound but comes and goes intermitanantly. I took it to the car wash and tried getting all of the ice out from underneath ( lots of snow and ice lately). The car wash had heated bays and when I came out it was gone so naturally I was thinking it must of been ice. But after the truck cooled down outside it came back. To me it almost sounds like a loose shield or something. I dont have the best ears and cant really hear it outside but not saying it isnt. I'd almost think that it is behind the dash or behind the firewall but like I said my ears arent the best but good enough to hear this thing whatever it is.It just seems like you have to have the right resonance ( think thats the right word). I really dont believe its anything mechanical. Maybe I'll have to let it warm up it my buddies heated shop and then take it out and see if she does it. Just one of things that drive you nuts, no what I mean? Anybody have and advice?

 

ta daaaaaaaaah I found my rattle. I crawled under my truck with the engine running and found the caulprit. The is a hard plastic/fiberglass heat sheild that sits above the exhaust pipe on the passenger side. Well this shield is "U" shaped and there was a crack in the vertical portion of this shield right next to the transmission. It would vibrate at the right resonance and rattle against the tranny. Well since there wasnt any real fixing the crack. I just cut this small portion out and VIOLA not more rattle. Man I'm glad I found that.These kinda things can really drive me up a wall.