Have a 91 f150 it has dual tanks i had to put a fuel pump in both tanks before i done that the front tank was pushing gas in the back tank so i put new ones in both tanks now the back tank works fine but when i select the front tank,the pumps comes on but the truck dies,it work fine before

Rodney Long

• 74 Answers
• Posted on Jul 04, 2008

SOURCE: 95 F150 2wd, interrupted fuel from the front fuel tank

my idea, the pumps are working agianst each other. what is the line pressure supposed to be? I think the rear pump is burning the new pumps up. is the rear pump running when the front pump is running? Let me know [email protected]

SOURCE: ford f 150 truck changing the fuel pump

check the fual canerst filliter

SOURCE: 1987 f-150 dual tanks fuel problem

You are right. There are three pumps. It sounds like the transfer pump in the front tank is bad. The in tank pumps just supply the high pressure pump to keep it primed. You need the front pump.

SOURCE: 1992 f-150 dual gas tanks tank closest to cab of truck pumps gas out the fuel cap

A FORD EQUIPED WITH DUAL TANKS THIS YEAR MODEL HAS CHECK VALVES IN THE FUEL PUMPS .THE FUEL RUNS FROM THE REAR TANK WHEN IT IS POWERED ON TO A TEE AND INTO THE SAME LINE AS THE FRONT PUMP . THE PROBLEM IS AT THE BOTTOM OF THE FRONT FUEL PUMP THERE IS A CHECK VALVE ON THE FOOT AND IT IS NOT WORKING.WHILE THE TRUCK IS RUNNING WITH THE REAR FUEL PUMP ON IT IS PUMPING FUEL INTO THE FRONT TANK . IT WILL RUN OUT OF THE NECK WHEN IT IS FULL.THE FIX IS SIMPLE REPLACE THE FRONT FUEL PUMP. THEY DONT MAKE A CHECK VALVE REPLACEMENT I CHECKED I HAD THE SAME PROBLEM AS YOU.

SOURCE: 1982 chevy truck with dual gas tanks with guage or tank problems

all you need to do is listen to hear the tank switching valve is working. It will make a soft noise under the rear cab section with the key on with the engine off. zif you do hear it sounding the switch your tank unit for that one tank you try to switch to is a fault. Sorry no illustrated diagrams are on hand, just knowledge