I have a 1985 mercedes 500 SEL that will be running fine then all of a sudden stall out, after awhile it will run fine again. I have changed the fuel filter and that seemed to help for awhile. Someone suggested the EGR valve but I don't know if it even has one. What can I do to stop the stalling?
If you are driving and the engine stalls for no reason or if you hit a small bump or hole in the road, then the first thing to do if you can is to have someone scan the computer system for any trouble codes stored in its memory.
Stalling can be caused by a bad crank sensor.
When the signal from the crank sensor is interrupted it will stop the ignition and fuel injector signal and stall the engine. Using a scanner and checking the engine functions like RPM, fuel injector pulse can help diagnose the problem area.
If you don't have access to a scanner you can go to your local Auto Zone auto part store, I think they will scan your car for free. Just check to be sure.
A faulty fuel system can also cause these symptoms but this sounds like it may be engine electrical. The use of a scanner can confirm this.
Let us know how you make out. If the problem is still happening then we can dig deeper into other systems that can cause a stalling problem in your car.
There are a few service bulletins on engine stalling, there are to many to list. You can access them yourself at ALLDATAdiy.com.