I was wondering when a fuel pump fails does it just quit working?

I drove to town 15 minute drive-parked-idled for 5 minutes, shut it off for 10 minutes, then it wouldn't start, I switched to the rear tank and it started.

I drove right home, and in the driveway I switch to the front tank while it was running and it quit. I never replaced fuel pump since I have owned the
truck in 10 yrs. Could it be something else? Oh its a 94 f150

thanks

 

Sure, why not? When they go, they go. Sometimes nice enough to fail in the driveway, sometimes not. If necessary give it (or the tank really) a good thump in the right spot with a mallet or something like that and will often get you down the road, or help troubleshoot.

 

Yes they can just fail , and often do . Check power and ground at the pump . I have seen a few switches melt at the plug ....

 

thanks for the reply. it runs fine on the rear tank, I checked all fuses(their good) not sure if or how you check a relay. and The inertia switch isn't tripped. If its electrical would it affect both tanks?

 

my rear pump primes up when I turn ignition on. but the front pump has no sound

 

Do I have to drop the tank to check for power or ground?

 

Depends on how flexible you are , . A lift would help . I have gotten to them to check without dropping the tank . Even changed some with the tank still installed .

 

thanks for your help by the way. I disconnected the harnass at the tank, and with a light tester (assuming red is power)I can seem to light up my tester

 

If you have power And ground , and the pump does not run . Pump is bad .

 

sorry I meant to say. I can't get power out of that red wire at the tank. could it be a bad fuel switch on the dash? is the fuse and relay and inertia for both tanks. Is the only break in power at the tank switch on the dash?

 

sorry me bad I meant to say I can't get power at the red wire.I just punched myself

 

Not sure on the wiring , without a diagram in front of me . Which is at the shop , 10 miles away .... You will only have power for a few seconds at KOEO . Should be constant while cranking . Someone manning the key is helpful .

 

I'll try that thanks

 

Used a mirror. and turned on the ignition. Yes I do get power at the connector. Must be a bad pump won't you say?

 

Sounds so . Do check ground to the pump also , if you have not already . But all signs of a bad pump . Be sure to change the fuel filter and sock when you replace the pump .