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1988 Ford Ranger Fuel Pump Problem


noahc00

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Riverside, CA
Vehicle Year
1988
Make / Model
Ford Ranger
Transmission
Manual
Hello. I have a 1988 Ford Ranger Custom 2.3L and the fuel pump won't turn on. I've checked and replaced the fuel pump and EEC relay and tested them. They're both good. I've replaced the inertia switch and tested it. It's also good. I looked at the wiring diagrams and followed each part that supplies the power and everything was checked out except one test and that was for the fuel pump connector. I bought one at Orielly's (Part # S2255) and replaced the old one. When I went to test for power at the connector, there was none at all. Each wire was giving out less than 0.5 volts and I'm confused as to why that's happening. I had someone else turn the key to the run position to test this and I'm all out of options as to what to check. I've seen some videos on YouTube of guys having a similar problem, and then finding out that it is one of the fuses called an EEC diode fuse but I don't think my truck has that. These videos are typically on the 1990 and 1992 Ford Rangers.

Also, I checked all the fuses and they're good as well.

Are there any suggestions as to what I can do?
Also, is anyone able to explain in a simple way how to apply 12V to the fuel pump directly so I can test to see if it is bad or not? That's the only thing I haven't checked yet. I heard you can do it with the EEC-IV System on the firewall of the truck but I don't know how to do it and don't want to try it and end up making things worse.

Any help is greatly appreciated, thank you.
 


sgtsandman

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Location
Aliquippa, PA
Vehicle Year
2011/2019
Make / Model
Ranger XLT/FX4
Engine Size
4.0 SOHC/2.3 Ecoboost
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4WD
Total Lift
Pre-2008 lift/Stock
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31X10.5R15/265/65R17
When I had my fuel pump issue, it turned out to be the fuse.

After spending all day troubleshooting the system and even pulling the bed with no success, I looked at the fuse again. The center part was intact but there was some brown residue on the pins. I replaced the fuse and the truck fired right up.

It was a very frustrating day.
 

alwaysFlOoReD

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When I had my fuel pump issue, it turned out to be the fuse.

After spending all day troubleshooting the system and even pulling the bed with no success, I looked at the fuse again. The center part was intact but there was some brown residue on the pins. I replaced the fuse and the truck fired right up.

It was a very frustrating day.
I'm laughing with you, not at you...
I've been there...
 

sgtsandman

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Vehicle Year
2011/2019
Make / Model
Ranger XLT/FX4
Engine Size
4.0 SOHC/2.3 Ecoboost
2WD / 4WD
4WD
Total Lift
Pre-2008 lift/Stock
Tire Size
31X10.5R15/265/65R17
I'm laughing with you, not at you...
I've been there...
Looking back, I can laugh. It wasn't so humourous at the time. All the f@#€ing work for stinking fuse...
 

ericbphoto

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Wellford, SC
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1993
Make / Model
Ford Ranger
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3.0 V6
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3.0L
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Manual
2WD / 4WD
4WD
Total Lift
6"
Tire Size
35"
My credo
In theory, theory and practice are the same. In practice, they are different.
One thing to remember, is that the ecu only energizes the fuel pump for a few seconds when you first turn the key on. That is to boost pressure for starting. Then it turns it off and waits for engine rpm to show the engine running.

For troubleshooting, you can get around this by using a jumper at the OBD1 data link connector. That will energize the coil in the fuel pump relay (with key in "run") so you can check for voltage throughout the circuit. See picture below. Use jumper wire from marked terminal to ground.

At that pint, I would check for voltage at the inertia switch. If you have battery voltage there, then you know the realy and fuse are good. If you have ot on the output side of the inertia switch, you know the switch is good.

If you turn the key to the run position, you should see the fuel gauge showing fuel level in the tank. That is from a separate power supply (gauge cluster) but it shares the same ground connection with the fuel pump. So, fuel level demonstrates that the ground connection for sender and pump is good. At that point, if the pump os still not running, it is either a bad pump problem bad connection at the pump.
20240131_093205.jpg
 

Oweb

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Boise Idaho
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1994
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Ford ranger xl
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Manual
Hello. I have a 1988 Ford Ranger Custom 2.3L and the fuel pump won't turn on. I've checked and replaced the fuel pump and EEC relay and tested them. They're both good. I've replaced the inertia switch and tested it. It's also good. I looked at the wiring diagrams and followed each part that supplies the power and everything was checked out except one test and that was for the fuel pump connector. I bought one at Orielly's (Part # S2255) and replaced the old one. When I went to test for power at the connector, there was none at all. Each wire was giving out less than 0.5 volts and I'm confused as to why that's happening. I had someone else turn the key to the run position to test this and I'm all out of options as to what to check. I've seen some videos on YouTube of guys having a similar problem, and then finding out that it is one of the fuses called an EEC diode fuse but I don't think my truck has that. These videos are typically on the 1990 and 1992 Ford Rangers.

Also, I checked all the fuses and they're good as well.

Are there any suggestions as to what I can do?
Also, is anyone able to explain in a simple way how to apply 12V to the fuel pump directly so I can test to see if it is bad or not? That's the only thing I haven't checked yet. I heard you can do it with the EEC-IV System on the firewall of the truck but I don't know how to do it and don't want to try it and end up making things worse.

Any help is greatly appreciated, thank you.
Hey I’m having a very similar problem on my 1994 ranger. On Reddit this guy told me to test the pump in A bucket of water with an external batter. So that’s where I’m at as well.
 

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