[2000' SOHC] Third fuel pump is broken

[CDW6212R]

Trace the two fuel lines there also, most likely they are both going to the fuel rail, which will lower the pressure(giving it a way back to the tank). It may have the 97-98 fuel rail, which will have the two fuel line connections, and a FPR set for 32psi(and a vacuum port).

That hose clamp can probably handle the low pressure 32-40psi range, if it's behind a barb/bulge in the line. But it would need to be checked on occasionally, they will become more loose over time. That's why hose clamps have never been put on EFI systems, due to the higher pressure than old carb stuff(5-8psi). There are repair fuel line ends available, which use the OEM type of line; there's a barbed end which is forced into the OEM plastic line(after heating it up).

The PCM you can easily remove and note the part number, and the 4-digit large letter code on the end. Post those and we can say whether it's a 97/98 computer, or the later 99-01 like the truck came with.

 

[slisman]

There is also one fuel line. Another line in black black protective pipe is electrical bundle and the blue one is probably vacuum. So there is no fuel return.

I've checked - no fuel pressure regulator on rail (which is logical - no fuel return).

PCM - thanks, I will check those digits.

 

[CDW6212R]

I'm sorry, I thought the picture showed a second fuel line. Checking to see that all the parts are correct is smart, the fuel line issue is only about the blue line though.

Without a return line, the tank FPR should build the proper 62-65psi with the engine off, just turning on the key once or twice.

How sure are you that the rubber hoses at the fuel pump and FPR are perfect, nor cut in any way? I had a slight leak at one of those connections in my 99 Explorer year ago. I went in to replace the pump, and also did the hose that came with the new pump. The pumps are very reliable, it's more likely that the issue is the FPR or a leak there.

 

[slisman]

Good point, thanks, I will check fuel lines when tracing blue vacuum line.
May small leak cause problems with fuel pumps? May they work harder to counteract leaks with higher pressure?

 

[CDW6212R]

Well, a leak would not be good for any of the system or parts. I doubt it would kill a pump though, they are made to push through that full pressure constantly. Heat building up from a low tank a lot, would do more harm to a pump.

 

[slisman]

Hi guys,
pump is not broken yet But I would be satisfied if this mystery were resolved.

So I finally purchased Haynes workshop manual and noticed that my fuel pressure is theoretically acceptable, also for models after 1999. See photo attached = my 2.2 bar pressure is acceptable and it is higher than minimum 30 psi.

Any ideas?
1) Maybe there was another fuel system - also returnless but vacuum dependent?
2) And as you wrote - should I check PCM number -> can it help and say which fuel pressuer/fuel system is allowed?
3) Maybe fuel pumps became broken because they were too strong - 4 bar. Is it possible that fuel pump is on too low pressure and it is killing it? Please consider that fuel pump was working 1,5 year after car purchase without any problems, only new installed pumps were killend withing 1 or 2 months. Maybe my fuel system should work with 2,2 bar pressure?

It's weird, but maybe we will clarify this issue - maybe it will be useful for other people with similar fuel system
Regards!

 

[CDW6212R]

If you only have 2.2x14.7psi than you don't have enough pressure. From 1999 up, all Fords must have at least 60psi, very close to that, 62-65 ideal. Your manual is wrong, it's mixing models.

Prior to 1999, the fuel pressure had to be about 32psi minimum, 35-42psi depending on vacuum present at the FPR, your 2000 truck has the FPR in the fuel tank.

 

[Turdle]

^^ Don, is this true for European models also?

 

[CDW6212R]

I think so, I cannot imagine that Ford would maintain the return fuel system past 1998. It is possible, but the many examples of non-US Explorers seem to all match our standard.

I read that he had a Chilton's manual, and those get a bad reputation a lot.

 

[slisman]

If you only have 2.2x14.7psi than you don't have enough pressure. From 1999 up, all Fords must have at least 60psi, very close to that, 62-65 ideal. Your manual is wrong, it's mixing models.

Prior to 1999, the fuel pressure had to be about 32psi minimum, 35-42psi depending on vacuum present at the FPR, your 2000 truck has the FPR in the fuel tank.

I thought so too, but reading this manual made me dizzy. You are right - FPR is in fuel tank. But every fuel pump change results in proper engine work - but with 2.2 bar pressure.

I think so, I cannot imagine that Ford would maintain the return fuel system past 1998. It is possible, but the many examples of non-US Explorers seem to all match our standard.

I read that he had a Chilton's manual, and those get a bad reputation a lot.

No, I had Haynes manual -> these one Haynes Manuals® 36024 - Repair Manual

Also I can agree that Ford would maintain return fuel system after 1998. And that is true because I have no return. As you can see on first page of this topic - there is no return fuel line to tank.

To sum up - we all can be right, my fuel system is tricky
May Ford services know what is going on? May they have knowledge/database with such information?

 

[CDW6212R]

I've never heard of the 99+ having low pressure such as the 33psi range you have, let alone the engine run with it. My 99 had an errant CEL every couple of months for a year, before I felt a power loss at high speed one day. Then I finally saw fuel pressure under 60psi. I was seeing right at 60psi the first 5-6 times I checked it, so kept thinking vacuum leak(CEL was 0171(lean)). When I saw the 55psi, then I knew I had an issue with the pump or the assembly, or clogged filter etc.

Mine was the rubber hose at the pump, a slight crack in it. For your truck, I'd seriously want to replace the whole tank assembly. I don't know what else could cause the pressure to be way low, multiple times. I wouldn't replace the pump if I assume you have more than one that are basically new. I know I'd rather buy the OEM assembly, but there are several other choices, much cheaper. I think the main difference would be possible fuel gauge inaccuracy, not the pump functioning etc.

 

[slisman]

You're probably right.
But I have few concerns:
1) Despite the fact that fuel pressure is 33 psi my engine was running properly and smoothly (also fuel trims were correct - too low fuel pressure would result in huge values of fuel trims). No codes present, no vacuum leak (vacuometer check), no air leaks (new intake manifold gaskets).

2) Replacing fuel tank assembly would be really good move. But there is one problem - I have no idea how to mount it. I've recently received new one from my friend (theoretically the one for 2000 Explorer - returnless), but there is no socket for this "vacuum" line. Maybe I should start from following this vacuum...

 

[CDW6212R]

You're probably right.
But I have few concerns:
1) Despite the fact that fuel pressure is 33 psi my engine was running properly and smoothly (also fuel trims were correct - too low fuel pressure would result in huge values of fuel trims). No codes present, no vacuum leak (vacuometer check), no air leaks (new intake manifold gaskets).

2) Replacing fuel tank assembly would be really good move. But there is one problem - I have no idea how to mount it. I've recently received new one from my friend (theoretically the one for 2000 Explorer - returnless), but there is no socket for this "vacuum" line. Maybe I should start from following this vacuum...

Can you take some pictures to show us your engine, the fuel lines, the vacuum line near the back of the fuel rail etc. It sounds like the truck has an odd combination of parts. We're basing our suggestions from it being a return-less fuel system.

 

[slisman]

Sure I will! Thanks for help.

This is returnless system for sure - only one fuel line goes from tank.
I hope after weekend tough winter will go away (-20 celsius degrees now) and I will be able to lay under my Explorer

 

[CDW6212R]

Ouch, you've got the real Winter we get for a couple of days at a time here, up north.

For the fuel pressure, what kind of testing tool have you used? I'm wondering if there is any chance that tool is not calibrated right, or the scale is different and being read wrong.

 

[slisman]

I think that there is no such chance - fuel pressure was measured by me and mechanic too.

 

[koda2000]

I confess I have not read your thread in its entirety, but as I'm sure you know, your fuel pressure should be around 65-67 PSI measured at the fuel rail. 33 PSI is way too low. On a 2000, the only things that could be effecting fuel pressure are the fuel pressure regulator (located in the tank, just above the fuel pump), the fuel line, the fuel filter and perhaps (though I doubt it) to some extent the fuel pressure damper located on the fuel rail. I'd be thinking either the pressure regulator is releasing fuel back into the tank at too low a pressure, or perhaps you have a leaking piece of submersible fuel line in the tank (pump to regulator, or regulator to FP assembly).

I've changed a half dozen Explorer/Mountaineer fuel pumps in the past few years (they all seem to die between 175k-200k). I use Bosch 69128 pumps exclusively and have never had any issues with them whatsoever. The 69128 kits come with new FI style hose clamps and enough submersible fuel line to replace both pieces in the tank, a jumper wire and a new FP insulator. So far I've not had any reason to replace the complete FP assembly.

I agree with CDW, that you should replace the whole FP assembly at this point, as I don't believe you in-tank FPR is available separately.

 

[slisman]

Thanks for another valuable opinion/advice!

Hopefully, I have new fuel pump assembly in garage.
But I have no idea what to do with this "vaccuum-like" line.
I should start form tracing it and finding where it goes.

 

[koda2000]

Thanks for another valuable opinion/advice!

Hopefully, I have new fuel pump assembly in garage.
But I have no idea what to do with this "vaccuum-like" line.
I should start form tracing it and finding where it goes.

Can't help you with that. Euro versions of our vehicles vary from our U.S. versions. There was a guy posting here 6 months ago, or so, who had some weird electrical device attached to his fuel pump assembly. The thing had failed and wouldn't allow power to reach the fuel pump. He couldn't find a replacement part and ended up bypassing it. He said it was some kind of anti-theft device.

 

[slisman]

Seems logic, another valuable opinion. No idea who can know such variants of US vs. EU fuel systems.

1) I've noticed that in Forscan PID "EVAPCV_fault" displays "yes fault". Any idea if it can be related with fuel pump? No error code, only "yes fault" in live data.

2) Smell of fuel near the tank. It is very gently, only when my nose is 30 cm near the tank. Can it be related?


Thank guys for your help!