Hi guys, I have a 1996 Sprinter 208D Motorhome and I'm having difficulty starting it after leaving overnight. It takes about 2-4 minutes of tuning the engine over on the key before it starts to try and fire up, whilst turning it over on the key, you can see it trying to gas up as smoke comes from the rear exhaust, then it tries to start and by keeping the engine turning on the key it splutters into life. I have changed the heater plugs (new of course) and recently a mechanic by-passed the relay and fitted a new one with a push button switch, but this had no effect, even with the button pushed for approx. 25-30 seconds. It just feels like there is no fuel coming through and after a couple of minutes turning the engine over it fires up, I have checked to see if fuel is coming through and it is and there is a live feed to all heater plugs. Any advice would be much appreciated.