I have a 1985 500 sel that shakes at idling and shuts down after driven a few miles. I tiik it to a mechanic all he did was change spark plugs, wires, distributor, and fuel filter. I admite the car runs a little better but still shuts down after the engine warms up. can someone help please???

 

Dirty fuel lines? Something leaky?

 

as in oil, air, what is it?

 

Our cars have a lot of vacumme lines here and there. Also check the mixture to see if it's running too lean.

 

Thanks I will check it out

 

get a new mechanic, he obviously did not fix the problem
It could be a multitude of things

 

Yes. My 1986 560 SEL had the same problems and the MB dealer did exactly what you had done to your car with no improvement. There was also a terrible smell of burning oil in the cabin whenever the car was not cruising on the highway. After checking under the hood I noticed the old oil filler cap (came with the car) is leaking quite a bit. This was replaced and unexpectedly cured the shaking problem. I discussed this with another mechanic and he feels this "loss of pressure" in the engine or "a loss of vacuum in the engine" was the cause of the shaking.

If your oil filler cap is leaking. Try a new one.