Recently my car began to die on me when under a half tank or so of gas, I suspected water in the gas due to the constant downpours we've been experiencing for the past month and the fact that it seemed to cut out during acceleration, deceleration or turning. I drained the tank only to find a negligible amount and the problem persists. When below a certain point, it may catch for a revolution or two but will refuse to stay started. Both fuel pumps are operating and the car starts and runs just fine save for some pretty bad intermittent (but present most of the time) hesitation. I have inspected for fuel leaks as well and have not found any. Has anyone else experienced a similar problem? What could I be in for?

 

Did you check the tube that goes from the pump to the pick up tube?

 

No, I haven't pulled the pump yet, but I will check that tube as soon as I get my hands on a fuel pump tool.

Update:
Last night it started sputtering on acceleration (almost to the point of dying) in addition to the hesitation. Fuel tank is nearly full...

 

Yeah you have a bad in tank fuel pump. What happens is when you first start the car and the pump is cooler it will work, then as the pump warms up it will get slower and slower cus its dieing. Add in the fact that its 90 degrees in florida right now and the pump will probably act bad all the time.

You don't need a special tool to remove the fuel pump from inside the tank. Just a hammer and a long flat blade screw driver. Thats how I've done it every time.

 

I was afraid someone would say that, I hope my exterior pump doesn't follow suit... My wallet already is home to moths and if I have to swing a $200+ repair even the moths will leave... I will be removing the pump and checking the pick up tube as soon as I have the opportunity, seems like pressure testing is in order for the in tank pump.

 

You can do some easy troubleshooting without removing anything. Get the car running and warm and put a piece of tubing into the tank via the filler tube. If the pump's sound is uneven, it is failing or it is sucking air. If your problem exists when the tank is nearly full, then the connector hose from the pump to the outlet pipe is not your only problem. As the previous poster noted, your pump may just be weak. If you leave it like this for long, you do place undue strain on the main pump and you may cause it to fail as well.

While the bung tool that iPD sells to remove the locking ring on the top of the tank is nice, it's not a must. If your car is originally from Florida or a like area, there's a good chance the nut is not frozen in place. Uncover the access area, blow off the top of the tank with compressed air and squirt some liquid wrench or P-Blaster all over the bung nut area. Leave it overnight. Blow it off again when you are ready to remove the nut. It's not necessary to pound on the two little tiny ears to get the ring off, there are larger teeth you can snag. Use a brass drift if you can. Steel is more likely to spark. Disconnect the wiring in the trunk and remove all the hoses first. Disconnect the flare-nutted line down near the axle first also unless you can disconnect it at the top. The return line is lower pressure and just has a hose clamp. With the pressure line disconnected down below, you can snake it around the top of the tank in a circle to help get the pump assembly out.
Good luck!
DS

 

Thanks dpsam,

I am aware of the strain a bad in-tank pump puts on the more expensive main pump so I'm not driving the car until I've replaced the in-tank pump. I will probably replace the fuel filter as well while I've got the fuel system depressurized. Hopefully when all is said and done my hesitation problem is cured as well.

 

couple random suggestions:
the bung nut tool makes it easy
http://www.ipdusa.com/product.asp?st...hStartRecord=1
I would replace the sock at the bottom of the pump, the hose between the pump and the metal fuel line, and the o-ring under the sending unit.
note the polarity (colors) of the pump wires becuase there is a good possiblity that black will be positive.
When I took mine out I dropped the plastic float into the tank

 

Thank you for the tips, I am more than aware of the dangers of the plastic float, I have dropped them into the tank on more than one vehicle and bathed in gasoline retrieving them. I will be attempting this repair today if the weather holds out.

 

Update:
I went to depressurize the fuel system and discovered that my fuse block labeling is wrong... I removed the fuses (4&6) that are supposed to be for the fuel pumps to depressurize the system and the car refused to die, but my radio went out... I'm guessing I have the wrong fuse block cover. Does anyone have a correct diagram for the 1985 244dl? The ones I've found on the internet are the same as the apparently incorrect one I have...

 

The label is correct (almost). Fuse 6 is not used on mid-eighties cars made for the US. Instead that fuse is the 20A blade one by the coil. Fuse 4 IS used for the in-tank pump - and you proved that the car will still run with the main pump only.

Here is another thing to try. Key on, car not running. Run a wire from the left side of fuse 6 to the left side of fuse 4. Both pumps will run, and you can hear them better because the car isn't running. Listen if the in-tank pump is sucking air (split hose).

Make sure fuse 4 and the contacts are clean.

 

Updated:

Ok, did that, heard the outside pump running... it's a loud buzz... However, with the key out, when I removed the jumper the pump didn't go off, nor did the lights on the dash until I started the car and turned it off again. This the same as the problem I'm having where if I turn the key to run and then turn it off and remove it the pump and lights stay on.

I can hear the in tank pump run, it's faint, but the sound goes away when I unplug it so I know that's what it is, it doesn't sound like it's sucking air either.

I pulled fuse 4, fuse 6 and the fuse near the coil and started the car, it died right away but I heard the main fuel pump keep running... I removed the fuel pump relay under the passenger side dash, still hear the main pump buzzing away... I know the relay is good because I inspected it and it's in good order.

Also, if I stomp the gas in neutral the car will sputter a little before it revs, sometimes it will "pop". It doesn't sound like a backfire, it's not loud enough. This symptom is much worse with the in tank pump unplugged.

So my in tank pump is alive and the relay is good, exterior pump is good as well but is loud enough to hear clearly and stays on until the car has been started and shut off when it is jumped or the key is turned on.

 

To avoid confusion and a really long post here is a summary of my car's weird behavior:

Turn key to 'on':
Tank pump and exterior pump run, dash lights come on
-relay removed same thing

Turn key from 'on' to off and remove:
Lights on the dash stay on, pumps keep running
-relay removed lights, pump, go off

Turn key off and remove from a running car or from the cranking position:
Pump turns off as expected
-same

Acceleration:
Bad hesitation, sometimes. If I floor it or push past 1/4 throttle at low speed car bogs.

Idle:
Engine rocks side to side a bit http://www.youtube.com/watch?v=Y2l3YiJNt-c. It idles pretty smoothly though. When it is dark you can see the battery, lambdasond and parking brake light will glow very dimly and go away as revs increase to around 900rpm.

 

nothing should be powered with the key out ... very strange

 

I know, it's a very strange problem. What's even stranger is when I jump fuses 4 and 6 with the key out the warning lights and the pumps come on, and they stay on when I take the jump wire off.

 

Have you seen the movie "Christine"?

Have you tried a different fuel pump relay?

 

Haven't tried a different relay, the one I have looks just fine when I open it up.

It looks like I've opened a can of worms here. I couldn't get the fuel lines off the pump and figured it wouldn't hurt to replace them so I cut them, no all of the sudden I've got a fuel leak from a metal line that runs from the in tank pump to the front of the car... On top of that I found a loose rubber hose coming from a metal line in the back of the car... that appears to drip gasoline... It looks like someone got ahold of this car before I did and really hacked it up.

 

I'm going to throw this one out there.

1. Have you pulled the felt under the steering wheel and kick panel on the drivers side and pulled off the fuse block to look for corrosion or wires with the jackets rubbed through? I would disconnect the battery, grab yourself a beer, grab a flashlight and just start to finger through all those wires under there looking for bad splices or damage. In fact look at as much of your wiring as possible. Even back by the fuel pumps and by the tank. Everywhere. Grab the wires, roll them in your fingers. Just be meticulous.

2. Have you replaced the fuel filter. I mean thats not causing your electrical issues, but could be part of your bog and hesitation.

3. Can you get a hold of a fuel pressure guage?

 

Here's what it all looks like:
http://img188.imageshack.us/img188/697/dsc0492.jpg

http://img194.imageshack.us/img194/6778/dsc0479n.jpg

Marked in yellow is the line from the in-tank pump that isn't held on with a hose clamp, which appears to go to the front of the car. This line is leaking where you see the circle.

Marked in white is the line attached with a hose clamp.

Marked in red is the hanging rubber hose I found, I have no clue where it came from or where it goes to, AFAIK there should only be two fuel lines back here... Picture two shows a third line-in to the tank, marked in red as well, is this where the hanging hose should attach?

adub,
1. Wires look fine so far, but there is a crappy splice where the fuel pump relay attaches... shown here: http://img23.imageshack.us/img23/4243/dsc0494v.jpg

I already re-wired the stereo due to it being hooked up with twisted wires covered in electrical tape... Looks like the previous owner really took the lazy route on electrical repairs... I hate electrical problems, I'm good with wiring, soldering, etc. but it's a pain in the butt.

2. Haven't changed it yet, I think I will since I have to redo the hoses anyway

3. I'm not sure, I think I know someone who has one but I can't get ahold of him

 

The red one in the second photo should actually be a cap. I think that it served some purpose on PRV motors. The yellow line is your return line since the fuel system flows more gas than it can use its necessary. White line i you line out. If the yellow line is leaking I would suggest fixing it for safety reasons.

I don't know why but undercar pictures make me dizzy so I can't look at the first phot o for long, so all my stuff up there is about the second photo.