I have a 1983 300SD and I think my turbo just went out. I was waiting at a fast food place and the engine was at idle. I heard a sound like my extra radiator fans came on but I was at 80c so that was not it. I didn't notice anything wrong going home, about 1 mile away. I got home and changed my diesel vacuum shut off valve that was giving me problems and my rear brakes and rotors. When I road tested I noticed the engine was sluggish, I can only get up to about 75 mph. and at that only very slowly. The only thing I can figure is that my turo went out. Any advice?