NO fuel pressure. Fuel Pump turns on still? | Ford Explorer - Ford Ranger Forums - Serious Explorations

  • Register Today It's free! This box and some ads will disappear once registered!

NO fuel pressure. Fuel Pump turns on still?

nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
A few days ago I just topped the tank off in my 01 Explorer Sport (4.0L SOHC). A couple of miles down the road the engine quit on me. Had it towed back to the house, checked the plugs, they all have spark. I sprayed starter fluid into the throttle body and it started momentarily and shortly died, so I'm pretty sure I have it narrowed down to a fuel delivery problem. I hooked a fuel pressure gauge to the schrader valve on the fuel rail and there the needle moved MAYBE up to 1 or two 2 psi, so essentially I have absolutely no pressure in the fuel line. I decided to check the easy solutions first and removed the fuel filter but it appears to be fine. When I turn the key to the ON position I can hear the fuel pump turn on so I had assumed the pump is still operable. Is there any other tests I can do to determine if the fuel pump is working without having to drop the tank? As I said before I have a full tank of gas so I would like to determine if it is something else before doing that. I had replaced the fuel pump less than a year ago. Is it possible the fuel pump is still turning on and not providing any pressure or is the fuel pressure gauge faulty? help please
 
<

Join the Elite Explorers $20 Gets rid of the ads!

Elite Explorer members see no advertisements, no banner ads, no double underlined links, can add their own profile photo, upload photo attachments in all forums, and Media Gallery, create and save more private conversations, and more. Join Today. Your support is greatly appreciated.




koda2000

Explorer Addict
Joined
September 2, 2011
Messages
13,852
Reaction score
1,502
Year, Model & Trim Level
x
the problem will probably be in your tank. it could be the fuel pressure regulator or the short piece of hose between the pump and the FPR. while your in there, i'd replace the fuel pump if it' original to the truck or has over 100k on it. if the problem turns out to be the piece of hose has split, or come loose, you can just replace the pump. if the FPR is broken you'll need to replace the complete fuel pump assembly.

FYI, sometimes you have to remove the Schrader valve before you can an accurate fuel pressure test, as the tester doesn't fully depress the valve. if in fact you do have around 65 PS of pressure, could it be you got a tank full of bad gas?
 
<



2000StreetRod

Staff member
Moderator
Joined
May 26, 2009
Messages
10,598
Reaction score
276
City, State
Greenville, SC
Year, Model & Trim Level
00 Sport FI, 03 Ltd V8
drain the tank

Since the pressure reading was 1 or 2 psi and the engine started with starting fluid it is likely that there is a problem in the fuel pump assembly. However, I agree with koda2000 that you should remove the Schrader valve core and measure the pressure again. 1 psi is enough to pump fuel to drain the tank. You could disconnect the line to the fuel filter and connect a hose. Then jumper the fuel pump relay contacts in the power junction box and the pump will run continuously when the ignition is on.
 
<



koda2000

Explorer Addict
Joined
September 2, 2011
Messages
13,852
Reaction score
1,502
Year, Model & Trim Level
x
Since the pressure reading was 1 or 2 psi and the engine started with starting fluid it is likely that there is a problem in the fuel pump assembly. However, I agree with koda2000 that you should remove the Schrader valve core and measure the pressure again. 1 psi is enough to pump fuel to drain the tank. You could disconnect the line to the fuel filter and connect a hose. Then jumper the fuel pump relay contacts in the power junction box and the pump will run continuously when the ignition is on.

using the pump would be a convenient way to empty the tank, but I've also managed to use a thin (5/16 ID) clear plastic) siphon hose by cutting the end of the hose at a 60 degree angle with a razor blade, and using a funnel to hold the splash valve in the filler neck open. I had to fold/bend the pointed tip of the hose and rotate to get it to go in, but it worked. the only thing that prevents the hose from going into the tank is the lip on the tank bung. it always seems to turn out that you have a failure when the tank is full. I just find it to be quite a coincidence that you just bought fuel and only made it 2 miles before it quit, but coincidences happen.
 
<



nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
Thanks for all the input guys. Koda, when I depressed the schrader valve, there was no pressure whatsoever but I will remove the valve and try the pressure test again. Also, it is very likely I got a bad tank of gas. What would be the remedy for that? Drain it and put fresh gas im there? Like I said it is a full tank and I just wanted to make sure I covered all of my bases before I drained it and dropped it but looks like Ill have to do that anyways
 
<



nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
Also I had replaced the pump last November but the assembly itself is original I believe with over 200k on it so its very likely the regulator has gone bad. Thanks for the input. I'll let you know what I find out
 
<



koda2000

Explorer Addict
Joined
September 2, 2011
Messages
13,852
Reaction score
1,502
Year, Model & Trim Level
x
well, if it turns out you definitely have no fuel pressure, it's something in the tank. if it turns out you do have sufficient fuel pressure then it's possible you have bad gas, but you wouldn't be the only one with the problem, in which case draining the tank would be your only option. i recently heard about a gas station where the deliver person put diesel in the regular unleaded fuel tank. that messed up a bunch of cars.

the FPR's job is to dump excess fuel pressure directly back into the tank. if the hose has ruptured or come loose it would have the same effect. the first thing to do is verify the pressure at the rail. it should be around 65 psi. if you end up going into the tank you're going to need to drain it either way.
 
<



2000StreetRod

Staff member
Moderator
Joined
May 26, 2009
Messages
10,598
Reaction score
276
City, State
Greenville, SC
Year, Model & Trim Level
00 Sport FI, 03 Ltd V8
coincidence

It would be quite a coincidence if your fuel pump failed at the same time you purchased a tank full of bad gas. It is unlikely that bad fuel would cause your fuel pump to fail. I suggest that you save the fuel when you drain the tank to check the fuel pump assembly.

Have you confirmed that the pump is no longer running?

Have you checked the electrical path (fuse, relay, inertia fuel shutoff)?
 
<



nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
Yes, I've checked the inertia switch, fuse and relay. I can hear the pump turn on and when I disconnected the fuel filter and turned the key to the on position, gas trickles lightly out of the fuel line which tells me the electrical path to the pump is working but for some reason, no pressure. I went ahead and drained all the gas out of it into a couple of 5 gallon gas jugs and will drop the tank tomorrow morning to inspect the assembly.
 
<



<



koda2000

Explorer Addict
Joined
September 2, 2011
Messages
13,852
Reaction score
1,502
Year, Model & Trim Level
x
please let us know what you find.
 
<



nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
I just removed the fuel pump assembly. All of the hoses appear to be in good condition. I can't determine anything wrong with it from its physical condition, but I would hate to buy a new assembly only to find out I still have no pressure.
 
<



<



RomeovilleIL

Explorer Addict
Joined
October 13, 2010
Messages
1,065
Reaction score
3
City, State
Illinois
Year, Model & Trim Level
98 LTD, 00 XLT
Bench test the pump. It may be bad, or have an obstruction in the pick-up sock. Remove the pump and sock from the assembly (one screw for the strap and the hose clamp, unplug the wiring). Put enough gas into a drip pan to cover the sock and run a short piece of hose from the top output back into the pan. Connect to 12 volts to turn on the pump. If it turns on and can hear suction but nothing coming out, pull the sock and retest. If still no results, replace the pump.
 
<



koda2000

Explorer Addict
Joined
September 2, 2011
Messages
13,852
Reaction score
1,502
Year, Model & Trim Level
x
well, do as 2000streetrod suggested and test resistance and power to the pump. i'm guessing it should be 12V initially. i think it's supposed to drop once pressure is up. not sure about that. the pump motor may run, but the impeller/turbine may not be working properly. if you have the correct voltage and a good ground going to the pump and replace the assembly there's really nothing else it could be. i don't like to replace parts unnecessarily either. it could just be the pump if the FPR looks to be in good shape, but i don't know of a way to test the FPR. maybe with compressed air??? about 65 PSI should make it through the FPR before it starts dumping excess.

what brand of pump is it? AirTex have a bad reputation, but i'm using one now w/out any issues after 2 years. most pumps have a 12 month warranty.
 
<



koda2000

Explorer Addict
Joined
September 2, 2011
Messages
13,852
Reaction score
1,502
Year, Model & Trim Level
x
Bench test the pump. It may be bad, or have an obstruction in the pick-up sock. Remove the pump and sock from the assembly (one screw for the strap and the hose clamp, unplug the wiring). Put enough gas into a drip pan to cover the sock and run a short piece of hose from the top output back into the pan. Connect to 12 volts to turn on the pump. If it turns on and can hear suction but nothing coming out, pull the sock and retest. If still no results, replace the pump.

sounds a bit dangerous if you make sparks near the pump. maybe use water instead just to test it. you can always flush it out with gas later if necessary. my money's on a bad pump at this point.
 
<



jremington59

Explorer Addict
Joined
October 28, 2009
Messages
1,934
Reaction score
2
City, State
Watertown, NY
Year, Model & Trim Level
1997, 99 and 2000 5.0's
Sounds like a weak pump. Years back I had a vehicle that the pump ran but didn't pump fuel it was so weak.
 
<



nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
Thank you for all of the suggestions guys, I really appreciate it. I can't remember the brand and as there is no brand name on it, I'm assuming it is an Airtex as that is the cheapest one NAPA carries on their site which is why I bought it as I was not planning on keeping the truck for much longer after replacing it, although I have found out otherwise. The FPR appears to be fine from outside appearances but not really sure how to determine if it really is working properly. When I look through the inlet on the FPR, and I can see what seems to be a diaphragm that is open. Should this diaphragm be closed? I will test the voltage and resistance on the pump when I get home tonight. Thanks again everyone.
 
<



nlikens

Member
Joined
July 11, 2011
Messages
32
Reaction score
0
City, State
Georgia
Year, Model & Trim Level
2001 sport
Ok quick update
Just tested the resistance on the pump and it was at 1.1 ohms. I hooked it up to a 12V jump box and it was reading 12.5 volts, bench tested it (in water as suggested by koda) and the pump was pushing the water through it, although I forgot to test it with the sock on it so I will have to try it again with the sock in place to see if it will still pump. At this point I'm thinking it may be the regulator?
 
<

Join the Elite Explorers $20 Gets rid of the ads!

Elite Explorer members see no advertisements, no banner ads, no double underlined links, can add their own profile photo, upload photo attachments in all forums, and Media Gallery, create and save more private conversations, and more. Join Today. Your support is greatly appreciated.




crunchie_frog

Well-Known Member
Joined
June 19, 2010
Messages
632
Reaction score
46
City, State
Johnson City, TN
Year, Model & Trim Level
Multiple 99-00 5.0 AWD
Just my two cents, if it were me, I would submerse your pump in gasoline to displace the water, corrosion to internals could take place pretty quickly. And yes, it sounds like your regulator
 
<



Top