4.0 extended cab replacement fuel pump- less range???

[Kirby N.]

Hey guys-

I have a 1991 ranger 4.0 manual everything extended cab. Recently the fuel gauge started working intermittently- so I decided to swap out the original fuel pump for a new one. It has 250,000 on it and has had very little issues.

I ordered a Carter fuel pump from rockauto for an extended cab pickup (larger tank) and it diss fix the intermittent fuel gauge, but it immediately had a lower mile range- as in I used to get 350 miles to the tank (I know because I was using the odometer instead of the fuel gauge), now I run out at 250. I figured maybe I got the wrong part so I returned it and got another one. Same brand, Carter. Which is supposed to be a quality part. And this one gets the same range- 250 miles- but it also reads 1/8 of a tank when it runs out.

When it runs out of gas it is finicky. It usually happens on a hill and I can typically get flat or let the tank settle and it will start.

I am baffled and ticked. I should have kept the old Ford one. Has anyone else had this issue? Is the only remedy a $300 motor craft pump??

Here is what my truck looks like:

 

[Bird76Mojo]

If you still have your original fuel pump hanger assembly then you could check it's depth compared to the new unit. Maybe the newer units are sitting at a higher level in the tank?




GB

 

[adsm08]

If you still have your original fuel pump hanger assembly then you could check it's depth compared to the new unit. Maybe the newer units are sitting at a higher level in the tank?




GB

That was my first thought as well. Nothing else really makes sense.

 

[Uncle Gump]

First off... Nice truck.

The question for me is... Is there 5 or 6 gallons of fuel still left in the tank when it runs out? The gauge reading seems to indicate that there is. If all things are equal... and the hanger/sending unit assembly is truly short... One would think the gauge would also read empty.

With that said... if it was just one assembly you replaced...it kinda sounds like it might have been bent. Not so likely that two assemblies gave you the exact same results.

 

[Kirby N.]

I quickly compared the original to the first replacement and then chucked it. The two new carters both looked the same- not bent or damaged.

Yes, when it runs out it has fuel in the tank- a few gallons. I used to run it all the way down to empty or 350 miles- now I start having problems at 1/8 of a tank and 250 miles. I thought maybe I got a regular cab pump but rock auto made me confirm vin and part number and everything.

 

[AdirondackRanger]

I'm guessing that what you thought was a completely empty tank was not.. did you verify with the old unit that the tank was empty?

Also other than the float arm being to high at this point.. I would be more inclined to think you have other issues with 250,000 miles. I don't know your engine history, but have you changed the upstream o2 sensors?

 

[Bird76Mojo]

One more thing. A lot of replacement fuel pump hanger assemblies you get, the ohm level on the gauge sender is a little off compared to stock. Out of the last 4 or 5 fuel pumps/hangers I've replaced or helped to replace, the fuel gauge never read the same after the swap. Seems really common these days.

I currently have two Rangers that the gauge now reads a little off from the way it did before changing the hanger assembly. Two different brands of senders too. It seems like the aftermarket can't get this s*#t straight for whatever reason.




GB

 

[Uncle Gump]

Did you ever put a MPG figure on any of your 350 mile range fill ups? Would be nice to compare that to one of your 250 mile range fill ups. At a minimum it eliminate or confirm the tank assembly for a sudden loss of range to a tank full. One would think there would be some symptom/condition that was associated with that kind of loss if it was indeed a driveability condition to "tank" fuel economy.

I feel your pain ... after all you replaced the thing to "fix" a malfunctioning gauge. At the end of the day.... some things aren't as much of a bargain as they appear these days. Fuel pumps/senders, wheel bearings, brakes parts and most recently... batteries are a few that I will spend it up front to eliminate "doing it again".

 

[adsm08]

It seems like the aftermarket can't get this s*#t straight for whatever reason.

Blame the OE makers and the Feds.

Aftermarket parts are made somewhat off spec because legally they either have to vary from the OE part a little or it is patent infringement. If they make them exactly the same they have to pay licensing fees to the OE part makers, and that would make their stuff the same price as, or more expensive than, the OE parts.

I'm not advocating the reduction or elimination of IP rights, but the OE jacks up the license fees to make it too expensive to make aftermarket prices to proper spec.

 

[Kirby N.]

Ok, so I think I figured this out.

My ranger gets about 15 MPG for whomever asked. Before and after the new fuel pump.

I ran the truck out of gas and I took the newest carter out and checked its depth and the tank depth. The carter was 11" deep. The tank was 12". So I went to the parts store and measured some pumps. All 11", until I checked a regular cab pump. 12" deep. I read online that carter pumps aren't what they used to be, so I ordered a delphi brand regular cab pump from rock auto. Installed it and everything seems to be perfect. I am now getting my range again. I have yet to run it completely out, but I think it will get to 350 miles.