'84 300D. I have noticed that the EGR area on the 603 engine needs to be cleaned of carbon. Does this hold true also on the 617 motors? When I blow air backwards into the switchover valve, it doesn't go through, and from what I understand it could be clogged. Can it be cleaned or do I need to replace it. The car has 202K miles, just replaced the rack bolt which smoothed out the rocking, but the idle seems more "rough" now. Will keep trying to adjust it. Also, HOW do you get the allen bolt on the steering box loose. This is a fairly new box, and the bolt will not move at all. Thanks for ANY ideas!
76 Cad Fleetwood