[rayporsche]

Sounds like a plan but then again how dirty they can be, do you have an oil leak in that area that bad ? the thing that you need to check for is their resistance values to find out if they are good......that been said there are so many variables such as their wiring harness, the connections and the wires itself, they must be thoroughly check, the resistance of the ignition coil must be check to see if it changes with temperature and some fuel components and things such as fuel pressure, fuel filter & pump, fuel pressure regulator and last but not least the fuel injectors for pulsation, their wiring insulation tends to crack up with the heat and years causing problems like the wires contacting and messing the continuity......and the list goes on and on but since you already ruled out the DME-Relay these other things could be the culprit of your problem or not. Good Luck !