recently acquired my first bimmer for $1300,(1987 325e 6cyl) overall in good shape, 182k. i've put in a new fuel filter, last owner just did platinum plugs. When i start the car and say hold the rev at 3000 rpm it will drop to 2700 and go back up and repeat, same flux happens at idle speed. Any ideas? also, manual crank sunroof is incomplete but rails spin, the black clips move up and down the rails but are broken on one side and missing on the other. I want to put a salvage roof in, do you have to remove headliner to remove the tracks that go into the roof of the car. any feed back helps thanks, jeff