Easiest way? F150 5.4L, How, where???

 

If you have a schrader valve you can use that but i don't think they put them on the fuel rail anymore. You can also pull out on the button on the fuel pump inertia switch inside the truck and crank the engine. Or you can let the truck sit for a couple hours and the pressure should go down by itself.


-Jon

 

The easiest way I have found is to disconnect the plug on the fuel pump inertial switch in the passenger footwell and then run the truck 'til it dies. Reconnect the switch when you are done (this is the Haynes manual way).

The Ford manual way is to use a fuel pressure gauge to drain some fuel from the test port on the fuel rail.

Do not try to disconnect a fitting with the system under pressure because it holds 30-40 psi in the system with the engine off.

Ian

 

The all time easiest way is to just let it sit overnight. I did that and had no pressure on the lines when I changed it out the next morning. You do have the special release tool, right?

 

I had a fuel pump problem on mine, so I monitored the fuel pressure at the test port. According to the manual, the system should maintain at least 30psi when shut off for 1 hour - I found that mine still has 30 psi after 24 hours of sitting. If your system drops pressure, you may have a weak check valve in the fuel pump.

Ian

 

I just pull the fuse for the fuel pump under the hood. Look in your book to see which one. Start it and it dies quickly. Pressure gone!

 

Very interesting. I didn't know that about the 1 hour thing. Well, I don't know what to say. I don't have any problems starting after it sits for a day or a couple days (rare). Always starts after only a couple revolutions. I think the pump does run when the ignition is first turned, but before you crank the starter. It must just build the pressure in that time before the cranking.

Thanks for the heads up.

 

just in case,keep that fire extingusher handy,5# or more is good insurance,and dont do any thing dealing with gas in a closed garage at the house,the combination of gasoline and your home water heater has added to our homeless population many a time