Fuel Pump? Fuel Filter?

[john1843]

2003 gt 4.6. Purchased about 3 years ago in the winter (about 25 degrees out) When I first had a look it started and ran great there was too much snow so I wasn't able to drive it then, went back when roads were ok and it wouldn't start so I disconnected a hose from the injection shot gas in , started right up and continued to run great the rest of the year. Put away for winter About 4 months, come next spring the same thing occurred, it been this way for 3 seasons until now, and always run great until now, it will start when I shoot it with gas however it won't continue to run, it might run for a few minutes smooth then rough, RPM's will fluctuate will it gas as soon as it starts to die and acks like it's starving for fuel.
Only fails if it sits for about 3 months.
Non ethanol fuel about 4 months ago (full tank)
I haven't listened for the fuel pump yet
Any ideas

 

[7991LXnSHO]

Listen for the pump to prime when you first turn on the key.
There has to be a way to check for fuel pressure with the 4.6.
Change the filter anyway, and recheck fuel pressure if still the problem.

I suspect the pump will not prime, or if it does, the pressure is not good. Has the pump made whining or worse sounds? It might need to be running in park for you to hear it.

 

[manicmechanic007]

By 03 the fuel pressure test port was gone on most Fords
You need a scan tool to check the fuel pressure transducer pid
On those you have 2 wires coming from the transducer on the fuel rail and no Schrader valve test port
I do not do this much anymore. I just replace the pump. I see no need as I have never seen a failure except for the pump
Yes there is a way to test the pressure at the filter using 1/4 inch hose (5/16 if you want to fight it over the barb on the filter)
So easy to put a pump in a Mustang. Buy a good one and yes replace the filter too unless you can blow thru it easy

 

[john1843]

Thanks, I did notice there is a schrader valve, ordered a pressure unit will have in a week. when you say easy to remove the pump don't you have to remove the tank?

 

[manicmechanic007]

Yes you need to remove the fuel tank. You can also just drop it down some and let it hang there while you change the pump