Running
 

I've got an '87 R-10 short wheel base with a 350 and dual tanks. My fuel selector switch was messing up, so I took it out, and since then my truck hasn't ran. I've put a new battery, starter, noc sencor, both oil pressure sending units in it, a new fuel relay, and a new computer as well as a new tank selector switch......... any ideas why the fuel pumps won't run when the key is turned on? any sugestions are greatly welcomed.

wow seem like you've eliminated most possibilities.
I guess you checked the fuses-
have you had a test light on the lead at the fuel pumps?
in other words, are you sure it's power to the fuel pumps?

what else have you checked?
are you able to get any stored codes?

Could be a problem with a ground on the tanks.

yeah the pumps are hot if you bypass the fuel relay. when the relay was bypassed, fuel would come up to the injectors, but then the injectors wouldn't fire. No, we wheren't able to get any stored codes because the socket for the 'check engine' light was missing, which we didn't know about. we changed out computers so the new one is clean....... we didn't know about the light until after we had changed the computers....

fuses?

yeha we got it fixed...... turns out that the parts store gave us the wrong kind of switch. They gave us a spring loaded switch, and we needed one that wasn't spring loaded........ Something little... figures. But it runs good now