I have a 2004 sprinter, it starts up normal in the morning and will start up if you turn it off right away and restart, but if it sits after driving it when you return after aprox. let's say 10min. it will not start. I check the fuel filter and found fuel is flowing, I check the fuel rail and found fuel going to the injector. I would keep trying to start tapping sensors and relays to see if it would start but it does not. I would try to start for about 5min then just like it would start. The engine is still hot so nothing is cool down to say that is the fault. I check the air filter the fuel filter and there is no check engine light. This happen about a year ago where the start and give it a rest and it would start just like that. At that time I tough it was the fuel pump so I change it but it still give the same fault, But just like that it did not give no problem for a year and just like that it started to give the same fault but this time I eliminate the fuel as being the fault.. if anyone found or have any idea to what is causing this please let me know..thanks..