fuel curcuit prob. reallllly need help

[jared87350]

i have and 87 pickup with duel tanks.
not geting fuel to the tbi.
fuel pumps have been replaced.
tank change over valve has been replaced.
selecter switch has been replaced.

i am able to jump the rely and pumps work.
is it possible that it could be the pump relays.
and can they both go out within a week of
each other?
if the relays are bad the selector valve wouldnt work right?or the pumps?

please help thanks

[SS Delux]

Try changing them out, when I did my clutch I had to replace the master and slave cylinder but it was working just fine before I pulled the tranny. Strange things do happen, especially with electronic equipment. Where in ontario are you located ?

[BIGJWEAVER]

hey ss are you still online.....

[babyJay]

Did you check the fuse for the fuel pumps?

[jared87350]

i dont have a fuse for the pumps.

[babyJay]

Originally Posted by jared87350

i dont have a fuse for the pumps.

Yes you do, unless someone bypassed it.

[wyattglock]

My fuse for the pumps is a 20amp fuse labeled ignition. I will take a pic and post it tomorrow if you need it. My truck has done some very similar things to what you are experiencing. To keep it driveable until I sort out the wiring, I ran my own relay and fused it separately.

[jared87350]

cool thanks . a pic would be great

[wyattglock]

Sorry I haven't got the pic up yet. Whole family is laid up sick right now, I just started to feel better today so I will see what I can do tomorrow.

[wyattglock]

Sorry it took a little to long.
The fuse for the fuel pumps are on the 20 amp fuse at the end of my high tech nylon pointing device. Hope this helps a little with your problem. I keep popping it because the contacts on the dual tank selector switch in the dash are loose and they keep dead shorting the circuit. So I am still running my own relay and only one tank until my switch gets here later this week.

[datguysaL]

wow, im so late to seee this... i had the same problem.. turned out to be the selector switch.

there is 2 types of switches.. there is the kind that returns to position after u select a tank and ttheres the kind that the switch stays in place when u select a side.

it took me a whole day to trace it to the switch when i had the same problem.

maybe its just your switch.

i never tried it but maybe if u hold the selector switch down while u crank. it could probly work as long as u hold the switch down.. it wont hurt, but its worth a try.

[wyattglock]

Originally Posted by datguysaL

wow, im so late to seee this... i had the same problem.. turned out to be the selector switch.

there is 2 types of switches.. there is the kind that returns to position after u select a tank and ttheres the kind that the switch stays in place when u select a side.

it took me a whole day to trace it to the switch when i had the same problem.

maybe its just your switch.

i never tried it but maybe if u hold the selector switch down while u crank. it could probly work as long as u hold the switch down.. it wont hurt, but its worth a try.

Thats what took me a while to figure out also. From what I have read about these switches, the momentary switch that does not stay in position is for carb'd trucks. This is sometimes called a 3 position or momentary switch. The 2 position switch is the one that is for fuel injected trucks. I would assume that this is the case because the fuelp pumps get their current from the relay through the switch. Hope you were able to figure out the problem with your truck.