Rather than revive my two year old thread regarding my 94 F150, 5.0, 4x4, dual tanks, I thought it best to start a new one since the problem is different than what I originally posted about. The current problem is that after replacing both fuel pumps and the selector switch, and everything working as it should, the truck started pulling fuel from the rear tank to the front tank, even if both were full. My questions now are: 1. Can I convert the truck to a single tank using either the front or rear tank? 2. If I can, would it be easier to use the front or the rear? 3. What parts would I probably have to buy in order to make this conversion?

 

There is a problem with the shuttle valve in the front tank unit.
If you only replaced the pump, you need to replace the entire unit (module) sending unit and all.

You have a convenient set up and it would be a shame to attempt to butcher it up.
It may also be lower cost in the long run.

 

Thank you, Hanky. I'll check that out since right now the truck won't start off of either tank.

 

I realize you did not ask, but if it cranks OK, pull a spark plug and that could tell us if you have a fuel supply or ign system problem.

If you have the tools and background to replace fuel pumps maybe we can offer something to make the problem easier to correct.

 

Checked today. No spark this time.

 

I would suggest start with checking all the fuses. It is no fun after doing a lot of unnecessary work only to find a fuse was open..

 

We'll give that a try, probably tomorrow. It's getting dark now. Thank you.

 

Okay. Have power from the ICM to the coil, one fuse replaced; but, no power to the distributor. I assume that's why there's no spark at the plugs. Could it still be a bad coil? Update: The coil, distributor cap and rotor have been replaced, and still no start. A test on the ICM found that with a test light, the light is off when the key is in the "ON" position, and 12.5 volts when the key is in the "OFF" position. So, my question now is, could the ICM be bad? There's still nothing to the distributor. My other question is, could this be the ignition switch.

TIA