I have a E-320 Wagon, 1998. Until last week, no problems. Now every other day or two or three, I'm having starting problems: the engine will turn over and over, without starting. This happens four or five times. Then after a short rest of a few minutes, I try again, andit starts. I might have twenty good starts, before I have a problem start. I replaced all plugs last summer. Could this be a fuel pump going bad?

 

When does the problem occure. It may be a crank position sensor.

 

it could be that there is no fuel pressure - bad fuel pump relay; mercedes fuel injectors not being fired - bad TDC or speed sensors. try to check it. update us regarding this matter. good luck