I have been having trouble recently with pulgs fouling on my 2001 Ultra 150. Had it in shop twice, both times, they replace the plugs and say can't find anything wrong, water test, runs fine. After 4 hrs, plug start fouling again. Always seems to be #1 plug, then #2. Appears to be gas starved and fouling from oil. I also notice the fuel filter is practically empty. Checked fuel lines, filters and check valve, all ok. Thinking the pulse fuel fitler is weak, given the order that the plugs foul (furtherest away first) and the fact that it can't seem to keep the filter full of fuel. If the pump is pumping correctly, shouldn't the filter be almost full?