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How to change your fuel pump.

92923 Views 131 Replies 69 Participants Last post by  JesusOnSkates
This write up was done while I removed and installed my new fuel pump.

Step 1. Disconnect the negative (-) battery cable.

Step 2. Raise and SAFELY support your van with either jack stands or ramps. The higher the better, also note that it does help to raise both the front and the rear of the van.

Step 3. I reccomend that you drain the fuel from the tank unless you have a quarter or less. This can be accomplished with a hand siphon or pump.

Step 4. Remove the splash gaurd from the driveshaft side of the fuel tank. It is installed with four press in clips and multiple slip on clips. It looks like this.
Step 5. You will need to loosen the fill hose attached on the drivers side of the tank. There are two clamps on this hose. It looks like this.
Step 6. It makes it easier to disconnect the fill hose if you remove the retaining screws that hold the fill hose in place inside the fuel door.
Step 7. Break loose but DO NOT remove the drivers side retaining strap bolts, on most vans the bolts do not need to be loosened as they are set from the factory to allow the strap to rotate freely once the bolts on the opposite side are removed, mine were over tightened by the previous owner or their mechanic. There is a hidden 15 mm nut on top of the strap where it attaches to the chassis. I have a needle nose vise grip on it in this pic to show where it is. I used a 12" extension and 15mm socket and a 15mm wrench to loosen these.
Step 8. Break loose the driveshaft side retaining strap bolts but dont remove them yet.
Step 9. Now is the time to support the fuel tank. I reccomend the use of either a transmission jack or a atv/motorcycle jack for this as it greatly eases the process.

Step 10. The fuel lines and the vent lines should now be removed from the hard lines. the two fuel lines require the use of a 5/8 line wrench and a 3/4 line wrench. the two vents are simple pinch clamps that can be removed with a pliers. Removing the rubber lines for the vents is a bit easier if the tank is lowered a few inches.

Step 11. Now it's time to remove the wiring harness. The wires run across the top of the tank and over to the drivers side they then follow the "frame" rail forwards and are attached to the body near the transmission. Unplug the harness and remove it from its retaining clips. Once it is free from the clips feed it through the hole in the "frame" and set it off to the side.

Step 12. Remove only the driveshaft side strap retaining bolts and then turn the straps 180 degrees out of the way.

Step 13. Now slowly lower the fuel tank being careful to make sure nothing gets caught and causes the tank to fall.

Step 14. Now it is time to remove the fuel pump / sending unit assembly. I accomplished this with a brass drift punch. Use the punch and a hammer to rotate the lock ring counter clock wise until it lines up with the notches in the top of the tank.

Step 15. Next you will need to remove the assembly from the tank be careful with this so the strainer does not fall off in the tank and the float arm does not get damaged.

Step 16. To remove the fuel pump from the sending unit you will need to remove the wiring harness and then push the pump up towards the top of the unit and when you have clearance tilt the fuel pump outwards and then pull down on it to remove it.

Step 17. Replace the o-ring seal on the top of the tank with a new one.
Step 18. Installation is the reverse of removal.

I hope this helps someone out there with there fuel pump job. Feel free to make comments on this post so I can make sure my details are as accurate as possible.
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My 2002 starts up fine, if it ran recently, but after more than a day or so, it takes many tries to start up. Mechanic (Firestone) says pressure goes to 0 overnight. Says they recommend a new fuel pump, about $1100, which I can't afford. I asked if it could be the lines and they repeated the recommendation. I've essentially no experience as a vehicle mechanic and a small toolbox, but I'm mechanically inclined - have rebuilt lots of things - worked on my wheelchair, computers...woodworking.

Any ideas? Having found this thread, I'm thinking it's beyond me. Seems well beyond me n my toolbox if a new fuel pump is needed. Seems worth taking to another mechanic. I don't know what to look for under the hood.

I could try to find someone (in/near San Francisco/Oakland) who'll do/help with cutting a hole in the floor... but while mine is a cargo van, the floor is covered with plywood, rubber and foam mattress, and more...

...and I just saved (the first page of) this thread to here - to archiveDOTorg, so if the picture host goes down, the images aren't lost, as has happened with other fuel pump threads. Good idea for well-illustrated howto's.
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Thanks. I don't think I'll be going that route - for those reasons plus beyond me, etc.
Any thoughts on whether something short of a new pump might fix the problem? Or does the loss of pressure overnight mean it's definitely needed?
Thanks! Ok, I'm going to pick it up now to avoid storage fee. (They say) I owe them $200 for the diagnostic - which now I'm thinking perhaps I should argue against - at least unless they've ruled out a leaking injector, regulator etc, which they didn't indicate they had done. I have a lot to learn - I don't know what fuel trims are or how I would prime the system. By pumping or flooring the accelerator at startup? Tank is 2/3 full at the moment, as I recall. Other than this, she's been running well - no major issues - (minor stuff - main cigarette lighter outlet doesn't work, some dash lights don't work, AC knob acts up, radio knobs were stolen, had to replace the flasher twice, because I put in LED bulbs, and then the first replacement didn't last.)
I picked it up and I haven’t been having fuel start problems since the “diagnostic”, and I noticed that the diagnostic said unable to replicate starting problem. On the other hand it also said ignition is arcing and sparking, and they quoted a gobsmacking $1500 for what I realized is a basic-not--complete, recommended tune-up. (plugs, distributor cnr, coil), which it needs. Plus the 1100. So instead I looked around and found a local place with a good reputation and I felt good with and I’m just getting a comprehensive tuneup, no fuel nothing.🤞🤞Hoping there was just some dirt in the fuel line that worked itself out. And adding a bottle of fuel system cleaner -could help!

Haven’t argued with Firestone about the diagnostic or that they noted the coolant was very low but didn’t fill it even though I had paid for a car care package. And Huckleberry, I’m thinking I’m pretty dumb if I ever make myself a customer there again?
I’d love to know when the fuel pressure requirements changed. (And I’m asking because I don’t know how to find out.)
Different set of years had different fuel pressure requirements….
Yeah, makes sense. This comment supports what you said and that people using OEM parts need to make sure they are using the upgraded part if needed! :
I used the Delphi pump, even though it was a little more expensive. It was the newer "upgraded" pump. It came with a little info sheet on what is new. The internal strainer, and I think 2 support rods instead of 3, and some other technical things that I didn't honestly pay much attention to.
Also I wonder if folks tried using a fuel system cleaner before doing this big job, and if it seemed to make a difference.
I’m just getting a tuneup (plugs, distributor cnr, coil), w/ NO fuel pump change.🤞🤞Hoping there was just some dirt in the fuel line that worked itself out. And adding a bottle of fuel system cleaner!
So it’s been six months and I should’ve followed up then, but anyway, just wanted to say that this worked! The shop I went to broke the engine cover(crack from by the radio on button to the floor), and didn’t say anything until I noticed, but far more importantly, she has been starting and running OK since then (‘till yesterday-but that’s for another thread-she needs a coolant flush, and there are lots of threads on that) I let it slide for $20 and hopefully some goodwill (ever the optimist)
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