I have a question regarding my 2002 Mercedes SLK 320 manual. Over a period of 2 years the car has failed a total of 6 times. On the first 3 occurrences the car would not start after a short break. Engine still warm, return to car, ignition on and all other lights illuminate as normal, but the engine does not turn over, just like an automatic not in park. No other adverse indications except (if you leave the ignition on) the radiator fan will start up and operate at maximum (sounds like a low flying Hercules). After an indeterminate amount of time (but always just before the recovery service arrives between 5 and 50 mins) the car will start as if nothing had happened. On the last 3 occurrences the engine has quit as I drove along, very inconvenient. Once at the roadside it is just as before, will not turn over. After repeated attempts (every few mins) it will start and I continue on my way. Mercedes has changed the ECU software for the latest rev. for £250. This has had no effect. Their diagnostic software shows no record in the car’s memory of any fault or abnormality. The fault has to date always managed to reset itself. Mercedes would like to change the ECU and charge me about £1,500. I am a little reluctant as they have no real idea, plus I believe it is just as likely to be some external transducer. Any ideas?