having some issues here recently
97 f250 ext cab long bed 5.8 4x4
for awhile ive had the problem of excess fuel from front tank returning to rear (doesnt really bother me much) however, on occassion while running on the front tank once it got below 1/4 tank it would act like it cant get fuel and run like crap and pretty well die if you stand on it. well today it started that again on way home, stopped and filled up tank and problem persist....any ideas? front fuel pump was replaced last year as old one was junk and didnt work at all. replaced rear pump about 2 months ago because truck would act same way on it and it runs fine on rear tank now(i mostly figured it was probably getting clogged up from junk in tank but i didnt find anything in it).

 

problem with front tank only is now so bad that truck cant even idle

 

may be wrong but i believe the pump went bad again

 

https://www.ford-trucks.com/forums/2...re-issues.html

check that page, is that problem similar to yours? if so this happens very frequently with these trucks with two tanks.. most people suggest just bypassing one of the tanks and using the other as the main tank.. hell i'd even drop the useless one and scrap it. save some weight

 

Have you changed the fuel filter? it's right there in front of the front tank

 

yes i changed the filter a month ago but i dont see why that would effect only one tank rather than both when they both have the same filter. also i can not hear the front pump prime which is why i think it is bad again.

 

nick, that does seem simlar but as i said i cant get the front pump to even prime? i searched all along the frame rail today folowing the fuel lines and only found one thing that may be the selector valve but no electrical wires running to it so if its the valve that would mean its mechannical and shouldnt affect whether or not the pump gets power. i mostly just want to fix the problem of not having two working pumps. excess fuel going to a different tank doesnt bother me seeing as how i generally only fill one tank anyways and can just switch to the other later to use the excess.

 

could be as simple as a bad fuse.. but that should make all of your fuel pumps bad.. have you replaced the fuel pump before?

 

There is no transfer switch. starting in 90 the use a fdm (fuel delivery module) in each tank. This is a high pressure pump. There is a check valve at each pump to stop fuel from returning into the tank that is not pumping. Apparently you have 2 bad pumps. the one in your front tank is not pumping. Checking your electrical connections first, That includes the switch in your dash. The check valve in the rear Tank has gone bad, and it will fill itself to the point gas will run on the ground through the fill neck.


You need to put a fuel pressure gauge on your system, I would bet your fuel pressure regulator is bad, and killing your pumps and check valves


I wasn't being smart with you on the fuel filter question before, just is a good idea to change the filter anytime you disturb a fuel system. Gunk gets picked up and clogs the filter, which will also kill a new pump.

Depending where you purchased your pump., it probably has a lifetime warranty on it.

 

yes both fuel pumps have been replaced, rear this past december and front was in early feb of 2010....found the receipt hopin it still had a warranty. also im thinking the regulator is bad too as generally it hasnt been holding pressure overnight, but im not sure how that would ruin the pumps?

 

If the pressure regulator is bad, it will over run the pump, and blow out the check valves.


A new pump is not always a good pump, I have taken them out of the box bad,it sucks to pull the same tank twice.

In your case, I would go for the front pump first, hopefully it's under warranty. then use the fuel out of the back tank first, so when you use the front tank, the gas has somewhere to go, until you can take care of the back tank. If you elect to do both tanks at the same time, it's just as easy to pull the bed.

 

actually if i ever have to do rear tank again im pullin the bed either way, i tried dropping the tank. had to get a jack and basicly lift rear of truck in air to get spare tire out, then had to grind all four bolts off for the plate above the spare and keep wiggling the tank aorund to get it just right for it to come out and go back in...lifting bed seems easier now...otherwise thanks for the help ill have to check info on warranty. pretty dure front tanks is up though

 

It's even worse when you have a class 3 or 4 hitch on, you have to take the hitch out too.

Good luck with it, let us know how you make out

 

i believe my hitch is a class 5 but it didnt get in way at all... maybe something to do with manufacturer