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It is a lot harder to replace the fuel pump than it is to connect a fuel pressure gauge to the test port on the LH fuel rail and see if there is any fuel pressure. If no pressure, check the fuel pump fuse and test the fuel pump relay. Check for pressure by turning the Ignition Switch to Run for 10 seconds and then back to Off, do not crank the engine. The expected pressure is 40 psi more or less.
Changing the fuel tank can be difficult if there is a lot of fuel in the tank and/or the bolts are rusty.
 

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Harry said:
How do you check the fuel pump relay?
If there is an identical relay in the fuse and relay box you can swap the relay.
You could use a 12 volt source to operate the relay and an ohmmeter to check the circuit through pins.
You could replace the relay with a ebay used one or get new one. I am reasonably sure this is the correct relay for your truck, Fuel Pump Relay - Part # 8971254411.
 

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The only component connected to the fuel pump fuse is the fuel pump. If you have the correct size fuse installed (20 amp) then the fuel pump must be defective and drawing too much current after it warms up.
 

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Buster28 said:
The only component connected to the fuel pump fuse is the fuel pump. If you have the correct size fuse installed (20 amp) then the fuel pump must be defective and drawing too much current after it warms up.
yep. diagnostics 101. check for high amperage draw, then determine if its wiring or the component/module itself.
 

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superswire said:
Buster28 said:
The only component connected to the fuel pump fuse is the fuel pump. If you have the correct size fuse installed (20 amp) then the fuel pump must be defective and drawing too much current after it warms up.
yep. diagnostics 101. check for high amperage draw, then determine if its wiring or the component/module itself.
But check that WIRING before you go and spend money on a fuel pump. This could be a visual inspection for a smashed / pinched, or chewed harness, and or unplug the pump at the tank and see if it still blows a fuse.
Most fuel pump failures I have ever seen involved the pump being OPEN circuit rather than shorted. Dennis
 

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DSUZU said:
superswire said:
Buster28 said:
The only component connected to the fuel pump fuse is the fuel pump. If you have the correct size fuse installed (20 amp) then the fuel pump must be defective and drawing too much current after it warms up.
yep. diagnostics 101. check for high amperage draw, then determine if its wiring or the component/module itself.
But check that WIRING before you go and spend money on a fuel pump. This could be a visual inspection for a smashed / pinched, or chewed harness, and or unplug the pump at the tank and see if it still blows a fuse.
Most fuel pump failures I have ever seen involved the pump being OPEN circuit rather than shorted. Dennis
But, please explain to me how an open fuel pump blows fuses ?

I have changed a few that have done the same thing. Especially on fords for some reason. Sometimes theyll pop a fuse and then run a while longer, but eventually they just completely short out. I agree with the majority failing open, but they do fail shorted too.
 

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Harry said:
Thanks for your help. It has 178K on it. Is it a hard job to replace the FP? Any tips?
Should I take it to a shop?
I believe you should have the DI engine right ? if so, i believe they have a low pressure pump in the tank as well as a high pressure pump. If you dont mind, i will ask somoene to chime in who owns one...
 

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I'll say this about fuel pump replacement in tank. I've done it on a Gen. one but really, I think what you'll run into would be the same regardless of car or year. I had access to a lift and a helper. I wouldn't do it any other way. I don't know if a Gen. 2 has a plug in the tank for draining like the Gen. 1 does but that's the first step. If your truck is a 4x4 you'll have to remove a rather heavy rock guard that protects the tank for off road use. And those bolts can be rusty and hard to remove. Then there are a few on each side that hold the tank in place. You'll have to drop it partially to disconnect the wires and fuel lines that are on the top of the tank. Then the rest is just lowering it and your in business. Renew all the fuel lines when doing this and don't forget to use the high pressure lines made for injection systems. Don't let me scare you off. This only took a little over an hour, but then I had use of a lift and a helper. Good luck. And as a safety note. Doesn't hurt to disconnect the battery. Removing any chance of voltage being where you don't want it.
 

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I've done this too many times, once on an 04 3.5DI and 5 times on an 00 3.2 (because I bought an airtex pump... dont.... delphi is recommended). First relieve pressure by valve on fuel rail with a rag or take the fuel pump fuse out and start to run gas out of lines to minimize gas spillage. I would not do this alone especially if you still have a good amount of gas left. If you have to do it alone, I'd buy a hand pump atleast and pump out as much as you can and you'll have to take filler hose off at the top of the tank , which have to be disconnected anyway to drop it. There's 2 bolts at the back one on the frame side and 2 or 3 bolt/nut in front. Becareful of the hard lines mounted on the side of the tank, ideally if you can balance it on a floor (helper assisted) and lowered it slow, you can unplug connectors/pop hard likes out if clips with a pry bar and pop them back in later(clips plastic so becareful). Once its down and all lines and connector disconnected there's a metal ring holding the pump down that you can tap with a punch counterclockwise to remove it. Make sure new pump comes with a new oring(required and def get a new fuel filter too). Reinstall is a little tricky since pump is spring loaded and have to get it just right to sit flush and Vaseline the top of the oring to make it easier to sandwich it. Get that metal ring started by hand enough to let go and use a punch to tap it counterclockwise to lock it back in. Reinstall lines and connectors then jack it back up there and start with the back to the front (since filler neck is at the back of the tank) and thread bolts back up there.
 

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Harry said:
So, those Delphi pumps on eBay for about $250 are the way to go?
Ordering on ebay may save you a few bucks, however you will have warranty issues. if you go on advanceauto.com and order a pump if you are a speed perks memeber or sign up to be one, you can use code JULY23 at checkout for 20% off making the delphi pump with a lifetime waranty (part number FG0289) only $235.

They also have a carquest lifetime pump for about $178 before the discount and i havent had any issues with those.

That way you can simply return it to yor local advance/carquest if you ever have any trouble and they can get you one next day rather than fighting with ebay sellers and shipping.

I would get a service manual or order a subscription for your vehicle at alldatadiy.com and diagnose it before ordering if it was me.
 

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Discussion Starter · #17 ·
Ordering on ebay may save you a few bucks, however you will have warranty issues. if you go on advanceauto.com and order a pump if you are a speed perks memeber or sign up to be one, you can use code JULY23 at checkout for 20% off making the delphi pump with a lifetime waranty (part number FG0289) only $235.

They also have a carquest lifetime pump for about $178 before the discount and i havent had any issues with those.

That way you can simply return it to yor local advance/carquest if you ever have any trouble and they can get you one next day rather than fighting with ebay sellers and shipping.

I would get a service manual or order a subscription for your vehicle at alldatadiy.com and diagnose it before ordering if it was me.
I replaced the fuel pump with a Delphi (25% off) and was about $250. Now my Rodeo runs fine. Thanks for all your help.
 
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