Hawaiian Brian

Hi guys,

I'm having a problem with my high pressure fuel pump that's located on my frame rail just below the driver. The Ford parts guy told me it was the isolator fuel pump, part # E7TZ-9C407B. I have fuel going to it, just not out of it. So, I'm guessing I need a new one. My queston is, is this fuel pump http://www.car-stuff.com/carparts/fo...ml#application going to work? I also can't switch tanks, and in turn, the fuel gauge doesn't work. When i bought the truck, the switch worked periodically. Now, nothing.

I could really use some help please!

Thank you in advance,
Brian

aliens8mycow

You might have several different issues here...

When you select either tank and turn the ignition 'on' (not started), do you hear the pump prime? It'll make a buzzing sound for about 2 seconds. I'd try both front and rear to see if either in-tank pump is working.

The guage is controlled by the sending unit, which will be mounted with the fuel pump in each tank. If your guage doesn't work on either tank, the sending units are bad (typical on these trucks).

These trucks have a confusing fuel system...

RocketScott

Yes you have several issues going on there.

Yes that fuel pump will work. Before you replace it do the check mentioned above. If you don't hear the pump going check the power going to the pump and all the connections.

Hawaiian Brian

the in-tank pump works, and I get nothing from the frame rail pump. I am going to see if it's a connection problem or not. I can hear and feel the in tank go on. It's difficult to check the reserve tank pump since I can't switch tanks. thanks for the quick responses. Should I buy a new sending unit? I'll post pics of the truck once I wash it, she's a beauty! She's just sick

aliens8mycow

So... the switch will flip to the other tank, but nothing happens? Does the guage move when you do that? Sounds like that in-tank pump is gone to me.

Just call me Sean

iTrader: (1)

You can bypass the switch to hot either tank to see if the in tank pump works. You can also hot the frame mounted pump directly to test it.

Hawaiian Brian

Sweet! It's all working now, I guess it was a clogged pump or something in the line. When I took the pump off the frame and tested it to the battery, it pumped what fuel there was in there. I reinstalled it, and the truck starts and runs fine! Now, my only problem is I can't switch tanks. The tank selector switch does nothing. The fuel gauge doesn't work, it will sit at 1/4 tank reading when the truck is off, and as soon as I turn the truck on the gauge goes right to empty.

Dominick

I am not to familiar with your year of truck so with that said I would be willing to say switch might be bad.
I only say that because I stupidly forgot to hook my switch back up in
my 95 and had same symptoms you described with the fuel sending units.

Ill add this in hopes someone can correct me if I'm wrong but only the diesels
came with selector valves?

Just call me Sean

iTrader: (1)

'87-'89 gasoline has a selector valve on the frame.

Dominick

Ok so then I don't suspect the switch now i suspect the valve cause its the valve that the sending units go to before being passed onto the dash.

Correct me if im wrong..