Fuel pump question

[Ragged out exploder31]

2001 Ford Explorer sport 4.0 auto . When I go to start I turn the key on and let the pump prime and when it quits I can try to start it but it won’t hit, but if I cycle the key on/off 3 or 4 times it will fire up , I’m thinking it’s could be either a bad/weak fuel pump or a bad check valve . I gonna check fuel pressure at the rail tomorrow but what’s everybody’s suggestion? It also stumbles real bad if you try to rev it up and it’ll die if you put it in gear and try to give it gas to take off

 

[Fix4Dirt]

my guess is weak pump, since it will not provide adequate vol/pressure when needed, but usually needing to prime multiple times indicates a valve. possibly both? id say replace the pump, however, since thats usually a good sign its about time.

 

[Motorhogman]

Had similar symptoms with my 2000 Sport along with the pump was fairly loud. Recently installed a new pump and it's by far quieter ( even with the access hole in the floor opened) than the one that did finally died.

 

[fast_dave]

@Ragged out exploder31​

These trucks are now over 21 years old, and have had multiple owners - when was the last time the fuel filter was changed?

Due to it's large size, it often gets overlooked by soccer moms and non-gearheads: i.e. "how can that huge filter ever get clogged"

From your post, it sounds like you have to build up the pressure to overcome to overcome a clogged filter (with the multiple key cycles)

Why not start cheap & easy - Explorer fuel filters are around $12 - Motorcraft or WIX...

If that doesn't work, at least you have a sound foundation and work your way up the parts ladder.

Look at it this way, if ultimately the problem is your fuel pump, you wouldn't replace it without also replacing the fuel filter - would you?

Hope That Helps & Happy New Year

 

[fast_dave]

PS - When you do replace your fuel filter, obtain a clear glass jar.

Get your old filter, and turn the INPUT END (coming from the fuel tank) of the filter upside down into the glass jar so that it drains out what has accumulated inside of it.

Leave it there for a few hours and watch what comes out - you'll be shocked...

Heck - take a pic and post it to this thread so that others may learn.

 

[donalds]

^^^^^ filter
That's why it starts and then shuts off not enough flow
@fast_dave is correct imo

 

[Motorhogman]

If you decide to change that filter I wish you better luck than I had with the so called "quick disconnect connector" on the fuel pump. After a week or longer of soaking it with WD and PB Blaster,. working it back and forth to no avail. It's sitting on the bench waiting for me to dissect it to figure out why it won't disconnect. Ended up cutting it off and replacing it with a dorman connector.

 

[Mbrooks420]

If you decide to change that filter I wish you better luck than I had with the so called "quick disconnect connector" on the fuel pump. After a week or longer of soaking it with WD and PB Blaster,. working it back and forth to no avail. It's sitting on the bench waiting for me to dissect it to figure out why it won't disconnect. Ended up cutting it off and replacing it with a dorman connector.

Most people don’t struggle nearly that much. I’ve gotten lucky and had them off in 5 minutes before.

 

[Motorhogman]

Most people don’t struggle nearly that much. I’ve gotten lucky and had them off in 5 minutes before.

I sure had no luck at all. There are lots of YouTube videos of people having to cut the lines to. Pretty common from what I saw there. One day I'll change the fuel filter and see if my luck has changed..

 

[Mbrooks420]

I sure had no luck at all. There are lots of YouTube videos of people having to cut the lines to. Pretty common from what I saw there. One day I'll change the fuel filter and see if my luck has changed..

I’m sure there’s also a lot of videos of people getting them off without cutting the lines, as well. I have found that sometimes it takes a different set of the release tools to work, and that the cheap ones are usually less effective.

 

[wiliamr]

2001 Ford Explorer sport 4.0 auto . When I go to start I turn the key on and let the pump prime and when it quits I can try to start it but it won’t hit, but if I cycle the key on/off 3 or 4 times it will fire up , I’m thinking it’s could be either a bad/weak fuel pump or a bad check valve . I gonna check fuel pressure at the rail tomorrow but what’s everybody’s suggestion? It also stumbles real bad if you try to rev it up and it’ll die if you put it in gear and try to give it gas to take off

My 2003 did much the same, would cranks and crank evenutally start. finally died and I had fuel pump replaced and new filter. It is now loosing power and seems to stumble and try to die. ANyone have ideas.

 

[Motorhogman]

I’m sure there’s also a lot of videos of people getting them off without cutting the lines, as well. I have found that sometimes it takes a different set of the release tools to work, and that the cheap ones are usually less effective.

There are plenty of videos of them coming apart as intended. Pretty sure the tools I have are industry standard for fuel, AC and transmission line couplers. What I ran into is clearly not the norm. That fitting has been soaking in a jar of PB Blaster and still has 0 forward movement. Corrosion, defective, or damaged from rotating back and forth, I don't know..

 

[Mbrooks420]

My 2003 did much the same, would cranks and crank evenutally start. finally died and I had fuel pump replaced and new filter. It is now loosing power and seems to stumble and try to die. ANyone have ideas.

How long ago was the pump replaced? What brand was it?

 

[wiliamr]

How long ago was the pump replaced? What brand was it?

It was replaced a week ago. Not sure of the brand of the replacement.

 

[EB4X]

"work your way up the parts ladder." I learned a new term for 2023 .... and have only been awake for an hour in '23

 

[Motorhogman]

"work your way up the parts ladder." I learned a new term for 2023 .... and have only been awake for an hour in '23

Hmmm has that replaced "when in doubt rip it out"

 

[EB4X]

/\ Now TWO new terms!
And one I learned here a few months ago, and my favorite >>> "Parts canon" ....as in shooting parts at 'er until she runs right !

 

[wiliamr]

Well, I started it up and ran the throttle up. The engine runs in a very exagerated lope. ALmost sounds like a low power midrange rev with a lower power drop in rpm. The rev Cycle repeating on a couple second basis. I checked. Fuel pump relay (seemed good) checked air filter it is newish (less than 2000 miles) I do not have a way of testing any of the fuel injection relays or sensors. Sooo back to the shop tomorrow.

 

[Ragged out exploder31]

my guess is weak pump, since it will not provide adequate vol/pressure when needed, but usually needing to prime multiple times indicates a valve. possibly both? id say replace the pump, however, since thats usually a good sign its about time.

Fuel pressure check and new fuel pump will be next the. . I replaced the filter first when I got it cause it was rusty and old looking also changed all six injectors, new plugs , wires , mass air , iac valve , throttle position sensor . I’m with Yal on thinking a new pump but wanted to get another opinion. How important are the two sensors behind the thermostat housing on the way it runs ? Both sensors have some rough looking wiring and I think I read something where one of them reports to the pcm for fuel/ air mixture

 

[Fix4Dirt]

Fuel pressure check and new fuel pump will be next the. . I replaced the filter first when I got it cause it was rusty and old looking also changed all six injectors, new plugs , wires , mass air , iac valve , throttle position sensor . I’m with Yal on thinking a new pump but wanted to get another opinion. How important are the two sensors behind the thermostat housing on the way it runs ? Both sensors have some rough looking wiring and I think I read something where one of them reports to the pcm for fuel/ air mixture

it will change AFR depending on the temp it reads. forget which does which. one goes to the cluster, one goes to the truck. if you have a scan tool you can see what the ECT is reading