Hello guys

I have a question for you guys on this side of the forum
My wifes truck a 2005 f150 4x4 has a problem
She went to work it ran fine when she went to leave there it wouldn't start
History on it
4.6 250000 miles it has had a random no start before like it wasn't getting fuel but after you try and restart it it would fire up and run fine.
now it wont turn the pump on at all. So I installed a new fuel pump and fpdm and still wont turn on even for the 3 sec prime.
Tach moves while cranking but will not build pressure to start
Tried swapping relays on the right kick panel. It said the inertia switch was on right side also but I couldn't find it

Any help would be appreciated

Thanks John

 

Does the theft light flash while cranking? Its probably a bad key.

 

No it does not

 

That is usually only an issue if you have been in a hard collision. After I had a collision @ 40 MPH, my fuel pump did not cut off. But give it a try.

Also check the owners manual for fuel pump fuses and relays. See if any of those are issues.

Maybe change the fuel filter. That could clog.

 

.....and for whatever reason, there was more than 1 owners manual for 2004 - 2008 The fuse panel is identical. But different fuses in different locations. So the fuse I was trying to change was in a different location. You could have been changing the wrong fuse.. The salesman at the dealership put the wrong manual into my glovebox at time of sale. My OBD II port and cigarette lighter went out. I had to go online to download the correct manual.

 

Was it badly corroded . The reason I ask is when I changed mine I had a hell of a time with its connector, the gasket rolled it it and it shutdown every few miles when it did start . Pulled gasket out years ago no more problems . Been thru floods and hurricanes never replaced gasket . Not saying thats your problem but others have had some of same . I made my own dwg of the inputs to pcm and FPDM because it is a complicated circuit on more than a few pages . But alias I have lost it now . The FPDM makes the final decision to start /stop fuel pump .
You know one signal is the fuel pressure sensor on fuel rail drivers side .
You also have connectors under the drivers side frame that are subject to dirt/corrosion . Plus there have been problems on top of fuel tank wires . You need to see if power from FPDM is headed to fuel tank input to eliminate that part of circuit . A faulty/intermittent fuel pump can be hard to find and test . I send you fuel pump relay circuit as there is grounds that feed it in right kick panel . They have corrosion problems there .
There are grounds on rear axle area for power back there also . I would clean these up .
But a test light or meter is going to be your best bet . Get your common for test right off battery to eliminate corrosion testing mistakes .

 

Thanks guys
I'll be messing with it again after work today. I'll try these things and let you know

 

Well I tried it when I got home and it started but died. Then no start just like last night. So I took the old pump and hooked power up to it and it ran so used it to see what prongs to hook up to on the pump in the truck. And fed power from a batt and made the pump run that way to pressurize the system and it did so I had the power stay hooked up and fired up the truck and let it run for about 30 sec. Plugged the factory harness back in and it fired up and ran ?????????
Then it was a off and on ...It would start and die like it was running out of fuel. ..I was talking with my buddy and he suggested I put di elc grease on all the plug ins .. Did that and it fired up and ran fine so I put it all back together and Im going tomorrow and have the muffler welded back on and drive it around before I give it back to the wife lol
I still don't know what happened in the 1st place to cause all this but I'm going to go with its running

Id like to say thanks for the responses guys

John

 

For future reference there is a fuel adapter plate on the fuel rail, passenger side. Just need an adapter to connect a pressure gauge..

 

there's also a FRPS = Fuel Rail Pressure Sensor located on the drivers side on the fuel rail. has a vacuum line connected to it . check and clean it. have you considered a new fuel filter ?

 

Im thinking driver module.

 

I'm thinking that it's a problem from 2018.

 

SMH..