Hi,

I recently purchased a 1988 Dodge Dakota that is in need of a new fuel pump/sending unit assembly. The original pump/sending unit assembly (P/N: 4203884) has rusted beyond repair.

I've attempted to find a replacement for this fuel pump/sending unit assembly online, but I have been unsuccessful.

I have been able to track down aftermarket fuel pump/sending unit assemblies for 1991 to 1996 Dakotas. Would an assembly from these years fit the fuel tank of my 1988 Dodge Dakota? Both use five pin electrical connectors, albeit different types, though I would assume I'd be able to rewire the connector for the new assembly.


The plastic on the rollover valve (the bottom connector in the first picture) has broken off, but it seems as if this is part of the EVAP system and not required. Could someone confirm this? I am located in Georgia where emissions are not mandated.


Thanks in advance.


Fuel Pump Assembly Connections

Removing Fuel Pump Assembly from Fuel Tank

Rusted Fuel Sending Unit

Fuel Pump Assembly Removed from Tank

Fuel Pump Assembly Removed from Tank

Fuel Pump Assembly Removed from Tank

 

Rock Auto has a fuel pump. In the FAQ section there is a thread where someone rebuilt their sending unit. I do not remember what year pump assembly it was.
here ya gohttps://dodgeforum.com/forum/1st-gen-dakota-tech/269286-diy-fuel-pump-or-fuel-gauge-trouble-shooting-no-dial-up-friendly.html

 

The problem is that where they fasten to the tank is a completely different design and the tank is completely different.

OTOH, you can find used 91-96 tanks in the boneyard sometimes; my master plan is to order a 22 gallon one from a 91-95 or 96, then swap my tank and fuel pump assembly out for the later one.

And then store a quality one on the shelf along with putting a new one in the truck.

I'm not sure what else will need to be changed; I THINK the filler neck; and I'll have to replumb the hoses a bit (need to use a 91-93 V6/V8 pump, or a 91-95 I4 pump, to get the return fuel system, for instance.)

RwP

 

I took a look at the FAQ and found some helpful information. Thanks for the suggestion! Here's the link to the fuel assembly rebuild for future reference or if anyone else has the same question.


I figured the mounting mechanism may have been different considering the tanks are different. As you've said, swapping tanks may be the way to go, and of course grab an extra just in case as they are somewhat difficult to come by.

I could probably get the pump to work with the original assembly, but the sending unit is the main issue. I've seen universal aftermarket sending units, and I am considering cutting a hole in the tank and installing a standalone unit rather than using the original assembly for both the pump and sending unit.


The plastic on the rollover valve (smaller outlet, circled in red) has broken off, but it seems as if this is part of the EVAP system and not required. Could someone confirm this? I am located in Georgia where emissions are not mandated. What is the larger outlet connected to? I can't seem to find a hose that goes to it.


Fuel Pump Assembly Connections

 

I think mine was capped; but I really don't remember on my 1988.

The sending unit may be repairable; I did mine, and it lasted another five years before it died again. (Hence my desire to swap to a 91+ assembly; the sending unit IS available for those, at least!)

RwP

 

I might mess around with the sending unit and see if I can get it to work, but it's in pretty rough shape.

As you said, 1991 and newer assemblies are available, and in that case, I'll search around for a fuel tank. I've found a website with fuel tanks for sale.

As for the rollover valve, it's possible there may not be a connection on the larger flange and it could have been capped off for the 1988 models, but for future reference, here's a picture from the fuel pump rebuild thread that shows the hoses connected on a 1993 Dodge Dakota.


Rollover Valve Connections

 

The 1993 is a different fuel pump assembly; I don't know where that goes.

Do notice the plastic ring that holds the fuel pump in place on the 1993; that's why we can't just drop it into our 1988s. Well, that, and a few plumbing changes ...

The small end goes to the fuel vapor line up to the carbon canister up by the radiator.

There IS one nice thing about our fuel pumps; there's a "DRAIN" fitting you can connect a pump to and suck the fuel out if you have to. Truck will run fine without it.

RwP

 

I found this construction in the tank of my 90' Dakota....