idealing question
 

I have a 2002 a6 4.2, When in Park or neutral the engine sounds really smooth, when I put it in gear, (drive,sport,triptronic manual) it sounds a little differently. Like a slight boiling sound or puttering, I cant hear it with music on or while im driving but I can hear it while at a stop, that normal? Just wondering I was thinking about changing the tranny oil any suggestions? anyone have any suggestions I think I might be paranoid.

Tranny fluid changed recently?

Nope, bought the car at 70,000 miles, havnt broken 80,000 yet its around 77,000 All I have done is change the oil twice, second day I got the car, and then over the last weekend. So change tranny fluid? thats what i was thinking. What about spark plugs? and if anything else, I know about the timing belt but that'll have to wait a little bit.

change the tranny fluid. Pull out a spark plug and see how they look, could be time for those too.