A couple of days ago i attempted to start my sei after the 4th or 5th go it started, since then it has been fine starting at the flick of the key as it always has done, could this be a fuel related thing, mabe something has worked its way through the system?? as it seemed as though no fuel was getting through when i was trying to start the engine, the keycode light went out each time i turned the key so i do not think it is an electrical problem ,should i get some fuel addative to flush through(if so what is best??) and or should i change the fuel filter, also where is the fuel filter and is it easy to change?? 1 other thing does the sump plug need a compression washer when changing the oil, many thanks if you can help.