The original owner 2004 Ford Expedition E.B 5.4. It is struggling to Accelerate and it's bad!! HELP!!!

[DLK1990]

The original owner 2004 Ford Expedition E.B 5.4. It is struggling to Accelerate and it's bad!!

These are the items I replaced:

• 8 Motorcraft spark plugs and 8 OEM coils replaced
• Replaced fuel filter
• Replaced Air filter
• Cleaned injectors multiple times (Chevron, STP, Seafoam etc.)
• Replaced EGR Valve (Duralast)
• Replaced ENR Pressure Valve Sensor (Duralast)
• Replaced Crank Shaft Sensor (Duralast)
• Checked hoses
• Replaced EVAC hose / green tip
• Replaced PCV and hoses (minus one in the far back)
• Replaced Airbag horn unit (horn burned out by not turning off. (Neighbors enjoyed the 3 AM horn blaring many nights until removing negative from the battery)
• Replaced Battery
• Replaced MAF (Hitachi)
• Replaced front and rear brake pads
• Replaced Serpentine belt
• Codes I could not get rid of until recently. They magically went away C1701, P0172, P0174, P0442, P0301, P0308, P0316,
• Codes that popped up P0231, P1000, and U1262
• Yesterday only
  • U1262
• The Expedition idles smoothly with no lifter noise. There’s no smoke (blue or white from the exhaust. I need help!!! I’ve taken it to two different service centers paying $185 and $175, to leave frustrated. No smoke test was performed.

 

[kep5niner]

Clogged cat? I had a similar issue and catalytic converter replacement was the solution.

 

[DLK1990]

It has pressure (exhaust) coming out of the tailpipe. If it was clogged would it be able to do that? There's no code and it recently cleared the cycle for that one. The EVAP has yet to do so... months later...

 

[kep5niner]

An exhaust shop can test the back pressure on the cats to evaluate if they’re clogged.

 

[Hamfisted]

Do you have a fuel pressure gauge ? What kind of fuel pressure are you getting at the fuel rail schrader valve ?
You should see 45-55 psi with the key ON.



.

 

[DLK1990]

I've attached the data files. Does anybody know what the numbers represent?

 

[Hamfisted]

I've attached the data files. Does anybody know what the numbers represent?

Means I need stronger glasses....

But the fuel trim numbers look fine.






.

 

[DLK1990]

Do you have a fuel pressure gauge ? What kind of fuel pressure are you getting at the fuel rail schrader valve ?
You should see 45-55 psi with the key ON.



.

How do I do this test?

 

[Expd830]

Have you cleaned the throttle body?

 

[DLK1990]

I've cleaned the to throttle body using the appropriate cleaner. It was dirty, and frankly it could be cleaned more. What about Fuel Pressure Regulator?

 

[GlennSullivan]

FUEL PRESSUE TEST

Rent, Buy or go to a shop with a 0-100 psi manual fuel pressure gauge.

Have the engine off.

Find the location of the Schrader valve on the fuel tail. Use a rag to let off the pressure built up in the rail. Screw on the gauge and have someone start the vehicle. Pressure should be above 40psi under all conditions. Low pressure would indicate bad in-tank pump, or clogged sock covering pickup area or possibly clogged fuel line.

 

[mbtech2003]

Unbolt the cats so they are loose drive it. My right one clogged up at 115k miles in my 05.

 

[keiferEXP]

Since you changed all those items, check fuel pressure. Sound like fuel pump, did mine recently not too bad with floor jack.

 

[cecilbridge]

I have a 2004 also. 2 things
1) Check if the Catalytic converters are blocked. Have an exhaust shop check it under acceleration. Normal idle might be OK, but under acceleration it’s blocked.
2) check if the front brake are binding - check calipers/hoses. My expy was having issues accelerating and came to find out the brake was binding. Had to replaced both from calipers and hoses. It’s a 20 year old vehicle so have the front hoses check.

Goodluck

 

[EngineerMike]

You had p301 & p308 misfires on respective cylinders, I didn't see that you replaced boots which can crack & bleed spark away

 

[Michael Philpot]

I had my leftside cats replaced due to a rattle. The right-side cats recently started rattling and I experienced very poor acceleration. I had it replaced and it fixed the issue.

 

[Michael Philpot]

Mine is 07 EB 5.4

 

[revrose48]

My 07 was doing the same thing. I had a tune up. It’s ok now. Try that.

 

[Michael Philpot]

My expy had exhaust coming out when idling. The catalyst was loose and blocking the pipe on the right-side. Since it has single exhaust, you will have exhaust at idle but lower pressure at acceleration from the tailpipe. The pressure before the cats will be very high at acceleration.
As for coil boots... that can definitely cause a misfire resulting in lower acceleration.
I replaced all the coils and boots due to a misfire and high mileage.