On my 1991 190E 2.6 it has a problem, that I would like some help with. If you start it every day, and drive it it's ok. However, if you start it, and go someplace, and leave it set for several days or a week. Then if you come back and try to start it. Well, you can grind it too death and it won't start. It just turns over like there is no fuel or fire & timing to be found. You can do this back and forth for maybe 15 minutes or so, and then you finally may hear kind of a pop of sorts. Then before long it will fire up and run. It will never fail this senario if you leave it parked for several days. Any help on this would be appreciated.