Been getting P0456 code truck runs fine for a few days then started stalling.
After a few cranks would start back up. Now two days later won't turn over.
Spray starter fluid in intake acts like it wants to start but nothing. Can a bad
fuel shut of switch be the problem or bad fuel pressure regulator. Replaced fuel pump a year ago. Please help.

 

The code P0456 is for the EVAP system. A fault in the EVAP system will not keep the engine from starting. If you had a fuel delivery issue then engine would fire up on the starter fluid and it's not. Therefore you are most likely facing an ignition issue.

How many miles on it and are the spark plugs the original ones?

 

Replace engine in 2009 only have 68,785 miles on new engine. Spark plugs have 68,785 miles also.

 

This truck is driving me crazy. Good fuel pump won't turn on. Check the relay and fuses they are all good. What could the problem be.

 

I guess I'll have to get it towed to a dealer since no experts out there.

 

This sounds like a job for Alloro anything?

 

If it won't turn over, sounds like a starter problem.

So, now it turns over, just not starting?

A bad fuel shut off switch would not keep the starter from turning it over.

A bad fuel shut off switch could keep it from starting, but would not keep it from starting if you sprayed starting fluid into the intake tract while you were turning it over. (See alloro's coment re: ignition.)

A ruptured fuel pressure regulator could keep it from firing up if it has completly flooded the system. You can try cranking it over with the throttle held to the floor to put the PCM in 'flood clear' mode to see if that helps. (I'm sorry, but I can't remember if the 2004 has a fuel pressure regulator or if it has the returnless fuel system where the FPDM contorls the fuel pump.)

 

If you now have no power to the fuel pump check the fuel pump fuse (or the FPDM if you have a returnless fuel system.)

You are aware that the fuel pump only has power for 2 seconds when you turn the key to 'on' if PCM doesn't detect a CKP sensor signal?

 

Like I said a few posts back, since the starting fluid isn't firing up the engine it's not a fuel issue it's an ignition issue.

 

Alloro the engine did fire up on starter fluid. And I took coil pack off and stuck plug in and it has plenty of spark. When starter fluid burn out of throttle engine shuts down. No pressure from fuel shedder valve. I'm not a mechanic but I know the pump is not pumping fuel to the fuel rail. Changed the fuel damper already(fuel pressure regulator) still no fuel being delivered to fuel rail. I'm new to terms like CKP sensor an where is it located, and what is a FPDM and where is it located.
The fuel pump fuse is good, the fuel pump relay is good, but I here the O4 has two where is the second. There is a relay that control the PCM, Fuel shut off and Fuel pump but manual says it is not serviceable have to see dealer can any body help before I have to shell out more money.

 

I know fuel pump is good because I dropped tank and took it out and hot wired it, ran fine stuck it in bucket of gas and it pumped fine. Should have hooked it to the return line and cranked the engine but had no help. That would have solve he fuel pump issue. Now what can keep the fuel pump from turning on? I'm scratching my head on this one.

 

My title should be 2004 expedition cranks but won't start?

 

Good work! You have identified the problem!

Can you hear the pump run for 2 seconds when someone turns the ignition key to the run position? (Sometimes if you take the fuel cap off and listen at the fuel filler pipe you can hear the pump do its 2 second prime.)

If you hear it run but it doesn't deliver fuel to the rail, what kind of shape is the fuel filter in?

If the fuel pump doesn't do its 2 second prime, get your DVM out and check for voltage at the pump. If you have voltage but no prime, check the fuel pump ground for a good contact.

If you don't have voltage at the pump, get your DVM out and a wiring diagram to help you to back track the fuel voltage supply circuit to find where it is open. Also check that the fuel inertia switch hasn't tripped. (check your owners manual for its loaction - you can check it with your DVM.)

The o2 sensors shouldn't keep it from starting so I wouldn't introduce more variables.

The CKP (Crank Position Sensor) is working since you indicated that you were getting a spark at one of the COPs.

And since you mentioned that you have a fuel return line you won't have a FPDM.

Good Luck and Happy New Year.........

 

Hmm, that's odd since in your first post you wrote, "Spray starter fluid in intake acts like it wants to start but nothing."

Giving two different answers to the same question impedes our ability to help you through this.

 

Found a blog called Sparky's Answers which a 2003 Ford Expedition has a no run, no fuel pump operation. After further reading Sparky suggested the problem was in the non serviceable fuel pump relay ford built in the fuse box assy. He suggested jumping the dark green/yellow output circuit for the built in relay. Tested circuit and no volt reading so I applied battery charge to fused jumper wire and truck started right up. Unhooked wire and truck died. Took fuse panel out and took it apart like sparky said and found that the internal relay that controls the pcm, fuse pump and shut off switch was burnt out, it was beyond repair and the mother board was fried where the relay connected to it. I have a new one on order and will keep posted. Looked on line but only found used ones so the dealer price is $362.75 but got it discounted for $304.75. Should be up and running in no time thanks to Spark's post. Thanks Sparky.