View Full Version : I'm stumped, 99 outback fuel related issue????????

07-24-2016, 09:50 PM
I have a 1999 moomba outback 5.7 GM motor, EFI. I'm having problems with the low pressure pump getting hot, and sending hot fuel to the water separator/high-pressure fuel pump. I've tried both, original gas tank feed and a alternate gas can. Both fuel supplies do the same thing. My high-pressure fuel pump will get up to 125, the hotter the high-pressure fuel pump gets the louder it whines. It will start to cut out intermittently around 2000 RPM. I believe the fuel is getting turned into vapor by the time it hits the fuel rails. At the fuel rails it's 135 To 140.

I have replaced the low pressure feel pump thinking that was the problem. The new low-pressure pump is doing the same thing. could the pressure regulator be an issue? Could the fuel relay cause this problem?

I had 40 psi at the rails during start up, but had to disconnect because fuel was going everywhere out of the Schrader valve

To me it seems like the bracket holding the low-pressure fuel pump is getting hot from the engine and transferring that heat to the pump itself has anyone else had this problem?

Thanks for all the help, greatly appreciated.