Mike, (myarmar)... the dealer did the fuel pressure thing and apparently it is in spec. And, as you suspected, the new throttle actuator was not the answer either.
The current thinking is that a coil may be breaking down under heat. If that it is the case, it would account for the problem manifesting itself after 1 to 2 hours of continued driving, and for the fact that the car runs fine after being shut off for a period of time. According to the feedback from the service rep, if the coil breaks down and there is no spark in the associated cylinder bank; that bank would essentially be pumping raw fuel thru those cylinders causing the extremely rich exhaust and smell.
In retrospect, the symptoms felt like the car had lost power, and then regained it, lost power, regained it, and so on. (surge, settle down, surge, settle down)
The service rep has a couple of coils on their way in, should be here tomorrow.
I am really starting to question the usefulness of the MB diagnostic devices, but as SteveBfl indicates, the diagnostic computer is just a starting point....not necessarily the answer.
Let's see what tomorrow brings.
A mercedes is an inanimate object and therefore must respond to logic and reason.
Last edited by mithra; 06-09-2003 at 10:49 AM.