2002, 156 noise between 2400 & 2700 RPMs
I have a 2002 Alfa Romeo 156, 1.8 liter engine. Regardless of the gear it's in, there is a somewhat loud noise. This also occurs while in Neutral and the engine is "revved". The noise sounds a bit like a chain being pulled from behind the car. IT also sounds a bit like - imagine this - a wing nut is loose on the air-filter housing and the washer is vibrating on the threaded post. The engine does not have an air-filter housing, but it does sound that way. Also, the noise is too loud to be a "loose nut and vibrating washer". Any ideas?