I recently purchased a 1994 E320 sedan with a 3.2L DOHC motor. The car ran perfectly for several month's and literally out of the blue began running horribly. I had it towed to the local dealer which informed me the engine harness and spark plugs were "coding", as the spark plugs were not the proper ones for the vehicle and the harness was damaged and had been repaired at one point. I had the harness replaced and the car tuned-up, fluids etc., and everything else checked out as new or in "new" condition. Within 24 hours the check engine light came on again and the dealer retrieved codes number 005 and 008, from the computer but stated that they were not "actively failing", only intermittant, and were old "stored" codes. The car runs very well, but appears to run a bit hotter than before (inbetween the line above the line marked 80, and before the the line approaching the red zone) I've read the posting on the egr valve and testing there-of, but how do I diagnose and where is the temperature sending unit (008 I think), and the EGR valve located on my engine?
Thanks