It was about 15¢ªF this morning and for the first time, my '89 750iL came with his loud noise from the engine. I can only hear it when I hit the brakes and when I try to turn. The power steering also gets hard, intermittently. Last month, my dealer suggested that I replace the filter but I haven't. Could that be the problem? Or is the belt just loose or could the bomb be bad? PLEASE HELP ME!