Last month a frustrated 928 owner was considering selling his Porsche since he could not count on it. Here is the rest of the story: After repeated test drives (over 400 miles) a pattern failure of starting and dying become more consistent.   A dip in fuel pressure was noted during hot cranking and attempted starts and a subtle “chattering” sound was heard under the hood.   With the sage advise of “Dave K” (a 928 guru) this led to the suspicion of a failing component in the Motronic computer. We sent the computer to a respected vendor for Porsche ECUs for evaluation. Their testing revealed NO PROBLEM FOUND with function. They did note that the circuit boards inside the metal box were not for the vehicle and therefore on-board diagnostics would not work, which we confirmed. With this information, and with a correct circuit board installed, our diagnostic computer would “talk “and the car performed perfectly.   To quote the owner, “in the three years I have owned the car, it never ran better and the symptom is completely gone”.   To hear that the computer repair shop could not duplicate the problem did not surprise me since the car had to be driven many miles before it happened. The ability to scan the car for trouble codes and install the correct computer was a viable risk to take and it paid off.   He is no longer selling it and the car is now getting a new interior.   MC

CategoryMasterCylinder, MC928