No idea what to do

[lorries93explore]

I have a 93 Explorer was running good but fuel gauge wasn't working. Changed the fuel pump...gauge working and truck ran great for 4 days. Then it didn't want to start and finally wouldn't. Changed fuel filter and fuel pressure regulator. No help...check fuel pressure which was 18psi. Changed fuel pump again. Pressure went to 33psi and has been running great for 5 days. Now problem is starting again....doesn't want to start cold, if I can get it started it runs real rough for a minute or so then smooths out. When it's warm...she starts right up. Changed the fuel pump relay...no help. Any idea what we need to check now? Thanks!

 

[NICE59FORDF100]

Are you getting any check engine lights when it wont start?

 

[lorries93explore]

No....no lights come on at all. Thanks so much for any suggestions you can give me.

 

[Roadrunner777]

Are you getting all these fuel pumps from the same place? It kind of sounds like you are getting defective fuel pumps, maybe all from the same bad lot. This can happen, the same factory worker gets incorrectly trained and he incorrectly rebuilds a thousand units before it gets caught.

Now, that said, there is a new symptom about starting in cold. It could just be that the fuel pump runs poorly until it runs for a while and warms itself up.

You are doing an excellent job of troubleshooting, keep it up, we can do this.

 

[lorries93explore]

Have been getting the fuel pumps from the same supply chain but from different locations. I just went out and tried to start it....took two trys instead of eleven from last night. It started sluggishly then ran smoothly....may be different next try. I have to get this figured out....it's a horrible feeling not knowing if you have a way to work every day.

 

[Roadrunner777]

For the next couple of starts, I would hook up your fuel pressure gauge first and record some numbers. First reading, just with key to on, don't start it.You may be able to hear the pump for a second or two. When it shuts off or at peak pressure, record that number.

Now, start the engine and record readings ever couple of minutes until it runs properly. I think, at some point, you may have to prove this pump is bad and see if they can get you one from another source. You will get more cooperation if you have actual data to back up your request. I know Orielly's stocks airtex but can get Bosch, that's the kind of deal you may have to do, is order a 'better' one. We will see. Post those numbers when you can...

Thanks!

 

[gmanpaint]

Bad Fuel regulator?

http://www.rockauto.com/catalog/moreinfo.php?pk=382258

 

[lorries93explore]

I will do it....will get back to you asap....Thanks

 

[Roadrunner777]

Bad Fuel regulator?QUOTE]

That's been replaced too. I'm leaning to the pump because a new pump seems to keep fixing it for a week. I wish I could get my hands on one of the failed pumps, that would tell all.

 

[Turdle]

Nobody mentioned the fuel filter--
or---
could be dirt--debris in the fuel tank causing a clogged fuel sock. A snickers bar will cause just this scenario--( had a friend get one in his tank from a disgruntled GF once)

 

[Roadrunner777]

It was replaced, mentioned in the original post. Multiple Snicker's, hopefully not.

 

[SwaintaN]

ok i have a friend that doesnt have an explorer but has a different ride, same problem, he replaces a lot of the same parts you did and even more. come to find out someone sand bagged his gas tank.... which kept clogging the thew pump, ended up clogging new fuel filter and injectors... cause he kept trying and trying like you are doing... but found out his Ex had her current b/f sand bag the motor... poured a couple cups of sand in, just something to think about if youve pissed someone off lately or if another ex looks like yours in town and they meant to do something to it

 

[Dano!]

a couple things you can try, before you put the new pump in, if you got a 12v battery for an electric drill, you can put the + and - from the pump onto the battery, and it will run the pump. i always do that as a quality assurance before i put a new fuel pump into the truck.

 

[Dano!]

the ground in your sending unit may be faulty, i had that issue with my Navajo, i replaced the relay, regulator, filter, pump and the sending unit, and i still had issues. what i ended up doing was hooking up my own ground from the fuel pump to the frame as a test. that way you bypass the sending unit as a ground. just put your own wire from the installed fuel pump to the frame and give it some juice. if it works you know your fuel pump is capable of getting electricity but the ground somewhere along the line is messed up and interrupting the flow of electricity.
if you try this and it works you don't want to do what i did on this thread
http://www.explorerforum.com/forums/showthread.php?t=298272
the fuel gauge is grounded directly to the sending unit, and if you make your own ground for the fuel pump your fuel gauge wont work. i had to do some re wiring to fix everything, if you find this to be your problem just pm me, and i can show you some pictures of what i did.

 

[lorries93explore]

Thanks to everyone for your suggestions. I have checked the fuel pressure I was getting 18psi then if I could get it started it would slowly work it's way up to 32psi and start running smoothly. Unfortunately, now it will not start at all....and the is no fuel pressure what so ever.