I have to turn the key once or twice for it to start. I just did a tune up and it continues to malfunction. One mech told me that it has to do with the fuel pump, but then another mech told me that fuel pumps on Mercedes are superb and doubts that is the issue. He said it might be a sensor issue. Any suggestions? Thanks.

A desperate 03' C240 owner

 

I would start with changing fuel filter first