Bajajay98

Have a fairly fresh 540 whipplecharged, when cold it takes 3-4 cycles of 10-15 second cranks to fire. The 2-3 cycle it will fire but run rough and stall. Once it's fired it runs great. And after it's warm and run you can shut it off and it will fire up no problem even after sitting quite a while. Seems to be only when I go to take it out after it sitting for a few days. Can't really seem to figure it out. Maybe fuel leak down or a computer issue ? TPS? I'm fairly new to the fuel injected scene.

getrdunn

iTrader: (7)

Can you ck fuel pressure to determine that's fine. Otherwise is a possible throttle position sensor.

Bajajay98

Fuel pressure gauge says 30 psi.

getrdunn

iTrader: (7)

If you don't have a pressure gauge you can purchase one cheap at any auto parts store. Usually kit comes with multiple adapters. Plus good to have anyway. My z71 truck acted up in same way you explained and it was fuel pump.

mike tkach

iTrader: (3)

what fuel pump are you running,also where is it mounted.it sounds like the pump might be loosing it,s prime after the boat sits for a while.

getrdunn

iTrader: (7)

Should have 50-55 min I believe. Injectors are probably not opening. I might be wrong on the pressure however Ido know that's was the case on my truck. I could get it to start but would run rough etc until I changed out fuel pumps. It was around 25 or so when I cked originally.

getrdunn

iTrader: (7)

Wouldn't it just reprime quickly though Mike. Fuel filter? Real basic I know but sometimes we do get lucky.

Bajajay98

Fuel pump is mounted right below the harmonic balancer by the front of the oil pan. I believe it's a aeromotive pump. I usually turn my power on, pump kicks on and will shut off after 10 seconds and then I try to fire the motor. I believe it kicks back on as soon as the pressure drops.

mike tkach

iTrader: (3)

i know that a1000 pump does not like to run dry,that is why i asked what pump and it,s mount location.is the pump mounted below the center of the tank.i am just wondering if the fuel could be running back into the tank.

Bajajay98

The pump is probably around the center height of the tank. But inlet line goes up and over a support and to the top of the tank below the floor. And the fuel filter is on the side of the motor around the same height as the valve cover. What about if I put a inline ball valve and after running the boat shut the valve and park it for a few days and test it out again?