[01KenneBellGT]

Yes I know this is for mustangs but its still a modular engine question. So 2004 Expedition, 234,000 miles and the engines never been opened up. Driving along tonight down the highway with cruise on and right before my exit I feel a couple big bucks like the engine lost power and kicked back in. So i think, that was strange, and coast the the stop sign. I get into it a little off the light to see if everything ok, seems fine, then 100yrds later I'm going up a small hill and it bogs like crazy, and just flat out dies. Kept good oil pressure (checked oil to and its fine) and the charging system had juice. It threw a code so ill check that tomorrow, but with a 5.4 with 234,000 what am i looking at most likely, timing chain is my likely guess.

 

[TheOdessa]

Honestly that thrown code will tell us more.

I had a 1999 Ford Explorer 4.0 SOHC motor do the exact same thing to me. Cruising on the highway at about 55 and it starts bucking. It ends up dying on me at a stop light and took 4 tries to turn it back on. I limped it into a Napa auto parts parking lot and started googling what the issue could be. Ended up being a fouled IAC.

Your timing chains could be the issue but honestly I couldn't tell you. I just did mine at 93k on my stang and the chain had started eating away at the metal. Some people never had an issue with it.

The code will point you in the right direction at least.

 

[46L281GT]

I had a 2004 expedition a couple of years, my bet would be fuel. It is a return style system so it could be either the fuel pump or the regulator. Like Odessa said, codes will help tremendously.

 

[01KenneBellGT]

I'll be getting a code reader in about 2.5 hours so ill report back what I find.

 

[01KenneBellGT]

Loaned a scanner and a fuel pressure kit the the auto parts store down the street. Hooked the pressure gauge up to the schrader valve and got nothing with the key turned and then I pulled 2 codes a lean bank 1 and 2. Seems like its just a fuel pump, which is very likely since its the original, and I couldn't hear it prime when the key cycles so that's the likely culprit. Ill grab my multimeter also and make sure its got power going to the pump first before I start tearing into anything. So much better news than a timing chain problem!

 

[TheOdessa]

Loaned a scanner and a fuel pressure kit the the auto parts store down the street. Hooked the pressure gauge up to the schrader valve and got nothing with the key turned and then I pulled 2 codes a lean bank 1 and 2. Seems like its just a fuel pump, which is very likely since its the original, and I couldn't hear it prime when the key cycles so that's the likely culprit. Ill grab my multimeter also and make sure its got power going to the pump first before I start tearing into anything. So much better news than a timing chain problem!

Ah there you go. The crappy part is you have to drop the tank to do it.

I had to do a fuel pump on my 99 explorer at 110k miles. That was fun. It's even better when it's full of fuel and you're doing it in a driveway. Thank God I have garage space now.

I used a cheap eBay fuel pump and it lasted til 176k miles when the engine blew the head gasket.

 

[01KenneBellGT]

Definitely a job I could handle but im currently at college and my tools/shop is 3 hours away, plus its hovering around freezing here in Iowa so i don't think a driveway repair would be much fun. Ill see how much the shop socks me for it and If im motivated enough I could probably get it done myself haha

 

[46L281GT]

Pm me if you need the procedure. I have access to alldata