breaking up / missing ?
 

I have been reading on here for a while but i have to ask for a little help.

Boat is a 98 Baja Outlaw 454 MAG MPI with a procharger aprox 500hrs

The issue i'm having is a weird miss. sounds like its breaking up. It does it under varying conditions. that's what puzzles me. It sometimes breaks up while accelerating from idle, if i pull the throttle back and then blast it full throttle the boat will jump up on plane run a few second then break up again. so it would suffice to say it does it all different times.

I keep thinking its ignition. Did plugs, wires, coil, cap and rotor. needed it anyway no change. changed the fuel filter/sep just in case. not water in it. while doing the cap and rotor noticed some corrosion in the distributor so i sprayed it with some electric contact cleaner.

any help would be greatly appreciated. i'm getting frustrated with this thing.:blaster:

Could be a loose rocker arm as well. Timing could be off in valve train.

Whats the fuel pressure doing when this happens?

the pressure was steady at 38 while running and would rise under boost condition.

i just went out to re verify after changing the fuel filter th epressure is low now approximately 18psi.

i bought the boat with this setup. does anyone know the fuel system routing with the procharger setup. is the factory pump retained.

there is a extra fuel pump and regulator mounted by the filter. im going to check the actual piping in he morning.

cant get the fuel pressure to go over 18psi messed with the regulator no change. pinched the return line no change.

maybe a bad pump

fixx
 

i most likely have a bad fuel pump, DONT RUN THE BOAT LIKE THIS you will blow the engine up..could be tha fuel pressure regulator but doutful,,looks like one of thease..could be seperate or a cool anodised one like in the pic's..http://images.google.com/search?num=...ac.fkdeL6wLmc8
you chould have 38 psi at idle then when you throttle up 1 lb of fuel pressure per every pound of boost so 43 ish under boost...