Hello,
fuel pump have no rail pressure but hear it prime. Installed new pump same condition. I pulled line off filter just a squirt then nothing. Swapped relays, checked inertia switch not tripped. Is there a pressure sensor on the rail?

 

Welcome to the forum

No, no fuel pressure sensor

I assume there is gas in the tank, have to mention that

New fuel pump with new assembly and "sock filter" at bottom of the tank?
And new inline filter in frame rail under drivers seat area?

Fuel filter has 3 connections, one from the pump, one for Return to tank, one that goes to the engine
If you still have access to the top of the tank, you can remove the two fuel lines and any of the lines on the filter then blow thru the line to see if either is blocked

Fuel pump only runs for 2 seconds with key on, but it does that each time key is turned from off to on

 

Hi,
I can get to top of tank and will try that. Does the PCM control rail pressure? Maybe that is bad. It does prime for 2 seconds but doesn’t build any pressure, can the filter just send it back to tank if the valve inside is bad?

 

No, there is no control of fuel pressure by the PCM, in 2005 it just assumes 50-60psi

No valve in the fuel filter
On the fuel pump assembly is a Fuel Pressure Regulator(FPR) and the fuel pump, also sender and float for gas gauge

The pump is capable of 80+psi, it sends that out on one line to the fuel filter
The other line, on that same end of fuel filter, sends that pressure(fuel) back on the other line to the FPR in the tank, the FPR has a spring valve set at 60psi, so releases any extra pressure(fuel) above 60psi onto the tank, so its just a loop thru the fuel filter, the "valve" is the FPR inside the gas tank
So on the other end of fuel filter there would be 60psi out to engine(fuel rail) at all times when pump is on

If the FPR was bad then could be 0psi, could also be a broken line IN the gas tank since you don't report smelling fuel

The Fuel system should hold at least 25psi pressure with key off for MONTHS and MONTHS


Picture here of a Ford fuel pump assembly, just general: https://m.media-amazon.com/images/I/61V-JLhBnML.jpg

Fuel pump is at the bottom, and half way up on the right is the FPR, the round thing
Blue thing is for EVAP system



And just FYI, Ford tried using same FPR setup but used it on the fuel pumps OUT line, then thru FPR and then Out to the regular 2 line fuel filter, simple
Picture here of that setup: https://encrypted-tbn0.gstatic.com/i...vF9IA&usqp=CAU

Didn't work too well, lol, but used from 1998-2000, fuel pressure at engine end could vary by 20+psi under high and then low engine loads, caused PCM fuel trims to jump all over the place

 

I thought I had a bad pump
so I replaced it with a complete sending unit. I have the same problem so it can’t be a broken line in the tank. Would pump prime if inertia switch is bad?

 

No, inertia switch passes 12v power to fuel pump, so pump wouldn't get any voltage if inertia switch was "open"

Battery(12v)----fuel pump fuse----fuel pump relay--------------inertia switch------------------------------------------Fuel pump---Ground

If you remove the two fuel lines on the top of the tank and turn on the key you should get fuel squirting out of one of the tank fittings for 2 seconds, if not then new pump is bad or blocked(can't pull in fuel from the bottom)

 

So, I removed the line coming out of the sending unit and when I turn key on it runs for the 2 seconds and that’s it it does not build any pressure. What tells the pump to run when engine starts?

 

That is correct, computer should turn on fuel pump but for 2 seconds only, it will do that each time key is turned from off to on
Computer won't turn on fuel pump full time until engine RPMs are above 400
Cranking speed is 200rpms, so engine must start before pump comes on full time

Its a safety thing, if there was an accident and a fuel line broke, the engine would stall, under 400rpms, and pump would shut off

 

So why can’t I get the engine to start? I can’t get enough gas in the line to start it.

 

Do 50/50 test
Spray fuel into the engine manually, gasoline, Quick start(ether), brake cleaner, ect.............
Try to start
If it starts, runs and dies, then you do have a fuel delivery issue
If it doesn't start then its a spark issue
50/50 instant results

Does you engine bay look like this: https://vis.iaai.com/resizer?imageKe...400&height=300

Loosen hose clamp at the air filter end of the air plenum that feeds air into the intake, and pull it up and odd air cleaner, spray in fuel, towards engine
Try to start
Better if someone can crank the engine while you spray in the fuel to keep it running
Once engine starts, above 400rpm, fuel pump should come on full time

If engine won't stay running then either injectors are not opening or fuel lines are blocked