00 5.4 recently long/slow to start

[08HybridOK]

So randomly (typically after sitting days) it takes 3-5x longer to fire. It's cranking strong, even changed the battery after a really cold day as its been problematic recently too, and 4-5 yrs old.

Going to key on for a few seconds doesn't seem to help (thinking I need to re-build fuel pressure). I haven't tested the pressure yet.

Seems to start fine later in the day after a bad morning. And it runs fine after starting. Feels like my old falcon, I just wanna pump the gas pedal; but being EFI I heard that is very bad! (true?)

I seem to recall changing the fuel filter recently; but didn't add it to my log, so the last reported filter change was in 07, 30k miles ago.

I'm going to start there, and grab a couple of relays at the same time just to have/test.

I'm assuming it's going to be the pump; but I get so confused on rockauto; they have parts ranging from $19 - $377 in the 'fuel pump' category.

I assume I need to test for fuel psi, pre-start (?psi), Key on/run (x/psi) and running psi. Is this right? And what am I looking for?

I have an 00, 5.4 4x2 (EB) originally had the air shocks; but swapped those out years ago. I seem to recall the tank is a 26gal.

Thanks for tips/advive/links. Tried searching; didn't find a similar issue; but "start" and "fuel" are broad terms.

 

[stamp11127]

You are correct to check fuel pressure first. Range is 35-45psi. If you are within range at key on engine off you are usually able to start.

Pressing the gas pedal with engine off doesn't do much other than wear components.

You can get a replacement pump or a complete assembly. I usually replace just the pump if there hasn't been a problem with the fuel gauge. Airtech pumps are junk according to the reviews. I've been using Denso without issues.

 

[american steel]

So randomly (typically after sitting days) it takes 3-5x longer to fire. It's cranking strong, even changed the battery after a really cold day as its been problematic recently too, and 4-5 yrs old.

Going to key on for a few seconds doesn't seem to help (thinking I need to re-build fuel pressure). I haven't tested the pressure yet

when you said sitting after days it takes 3-5x longer to fire, does this mean the engine does start and run? if so don't worry about it. you must remember you have a very old vehicle cold weather will do this. my brothers 2007 GMC 5.3 does this.

and no using the gas pedal will not do anything.
it only opens the throttle blade that's it. engines love cold air but everything else doesn't (your sensors)
check your fuel pressure, you installed a new filter this shouldn't do anything. your pump may be on its last leg here.

 

[08HybridOK]

Thanks, I'll get a gauge soon. They rent at the chain stores?

No running, just cranks for several seconds. While out yesterday at a store, come back out and it started, but quickly stalled, and was hard to restart. Stalled again. Finally 3rd attempt it started fine. Its has only done this once.

 

[08HybridOK]

So assuming it is the pump, is this the part I need to order? ie Has everything I would need to do a once & forget it job?

DELPHI Part # HP10131 $125

or just a pump & strainer for $83

If I'm going through all that work, I think I should replace everything. (I have a 99 Ranger that the fuel gauge stopped reading properly, so I assume this ones not fare behind, and with the digital odometer not displaying 90% of the time I need a working fuel gauge!)

I don't suppose they both use the same pump? Could I get a whole new assembly for the ranger, then put that pump in the Expedition?
(99 ranger, 3.0V6 Flex Fuel, extended cab 4x2)

 

[stamp11127]

Why assume the pump? Prove it is the pump then replace if needed.

 

[08HybridOK]

I just want to know the right part# if it is the pump. In past experience sometimes these messages can take a while to get an answer, while other times its just minutes. I just want to be prepared so I can order the parts to fit my work schedule, if needed.

 

[stamp11127]

Part number depends on the suspension. I usually just change the pump, but it is your call.