Ok, so I have a 90 f150 L6. dual tanks... Was driving down the highway and truck just stopped getting gas, no sputtering or anything, just up and stopped. Yes there is fuel in it. Truck didn't die immediately, only actually died when i pulled over and stopped moving. I Had a similar problem a couple of months ago, thought it was the fuel pumps, so i replaced one of them with a brand new one, but turned out to be a bad fuel tank selector switch, which i bought for $15 and a Junkyard. So I pulled off the selector switch and tried just to jump the contacts to see if it was the switch again, no dice.. gas gauge moves but I dont hear either pumps activating when i turn the key forward. I shot some Starter Fluid into it and it started up for half a second. so i know it a fuel delivery problem. I'm thinking an electrical problem somewhere... any ideas, anyone know a good spot for the Wiring Schematics for my make and model... i'm stuck!!!

 

I'd check the fuel pump relay first. look in your owners manual for location but theyre usually pretty accessible. they can get funny before they go like you said or they can just go. A relay is bacially a switch. Its purpose is to take the power from the ignition switch and up the amperage to the level necessary to drive your fuel pumps. It will be a little black box about 1.5" cube that plugs into a harness somewhere or or it can be with your power distribution ie. where all of the fuses are.

Cheers!

 

have you tried resetting your inerertia switch?

 

A couple months ago when I switched out the fuel pump, I changed one of the relays. there are two of them in the same spot right next to eachother in front of the firewall. I switched out the other one today...

And what and where is the inertia switch... and how...

 

the inertia switch kicks the pumps off if it thinks theres a hazard. its a safety device. yours is either under the dash above the brake pedal or on the passenger side somewhere. you press the button(s) simultaneously to reset it.

 

i'll give it a try in the morning, let ya know, thanks

 

ok, so its not the inertia switch, got up under there and found it on the drivers side. one red button on top which was already depressed. pulled the connecting wires off... jumped them... and still nothing...

 

Try turning on the key and releasing the schrader(sp?) valve on the fuel rail and see if that release in pressure fires up the pump. The pressure switch in the fuel line may be sticking. not sure where it is but there must be one somewhere.