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1985 Mercedes 380sl

My 85 380sl with 132,000 miles has an intermittant dying problem. This started when engine was cold, usually after trip to the neighborhood quik mart and would die on the way home (appx. 1 mile). It would have to set for 5 minutes or so then would restart and all fine. This happened 2 times per week and sometimes not for a month. My mechanic kept it for a week and encountered same prob. He suspected fuel sending unit behind glove box. We replaced it. Now dying has only happened when engine temp is around 85c (not quite warmed up) but it will restart within 1 minute. The tach, at this temp,does a surge to 3000+/- when engine is really at 1000rpm. Engine is not surging just the tach reading. Tach issue has be less frequent than dying issue.

Not familiar with the 107 chassis, so I’m not sure what the “fuel sending unit” behind glove box is. Could it have been the fuel pump relay? That’s what I would suspect, along with the OVP (overvoltage protection) relay for erratic starts and dying. Does the ABS light come on when operating the car? How long has it been since the car got new filters, plugs, wires, distributor cap/rotor? Tach must be controlled by some sensor (TDC signal?) that has a problem.

You will have better luck getting an answer if you post this on an SL forum (google for them), there are several with lots of knowledgeable members.