I just noticed that my oil service light recently came on in my 88 325is. The "oil-low" light is not on, but the yellow light is (below the tach adn between 3 green and 1 red). The car runs great, but I do not want that red light to come on. Can anyone steer me in the right didrection as to what should be my next step, without getting screwed by shady mechanics? Thanks to all that respond.