Video here, It's 1986 325e I can't put my finger on the noise but I was hoping for some help if someone has heard it before. It's apparent to me because I hear it everyday but I'm focusing on the most high pitch thing that for lack of an explanation goes: 'guh guh guhguhguh guh guh' or sounds like a chugging noise? I can answer question or rev, but the reaction is this on idle I hear it, then give it some gas goes away still there in the back ground but very faint. I want to make a super eta with a turbo so I'm gonna go in there and be shuffling around but I was hoping someone might have some insight.