MAINEiac

so i think my fuel pump is bad. going to test it directly while it is in truck. i just unplugged the harness and there are two spade terminals in the plug. I am assuming the pump is grounded thru one of these spade/wires or is the pump grounded thru the tank? I have an extra car batt handy so i can test the pump.i have the batt grounded to the truck and have a 12v test light lead from pos.batt terminal ready to contact one spade at a time at the pumps plug. I have done this already and one spade made the test light come on so that would be the ground. the other spade nothing happened.
**My question is does that tell me the pump is bad or do i have to run another lead from the negative spade in the plug to ground it and then touch the pos test light lead again to the other spade to see if the pump runs?**

GSGALLANT

The ground comes from the terminal, and is the one that lit your test light when you did your test (white wire with black stripe).

The other wire on the terminal (blue wire, I think?) comes from the circuit opening relay, and would have approx 12V on it only when either of the two following things happens:

1. Starter is cranking (ignition to "START" position).
2. The flap in your Volume Air Flow Meter (VAFM) is open.

So for your test, just disconnect the battery ground from the truck, and bring the battery to the back seat. Connect the battery ground to the correct side of the terminal on the pump itself (you already found which wire is the ground wire on the other half of the terminal with your test light, which would be the white wire with black stripe... just make sure you are matching that up to the correct side of the terminal on the pump itself.)

Next take a positive lead directly from the battery and touch it to the other side of the terminal on the pump itself. The pump should start.

If the pump works with this test, connect the fuel pump connector back up, install the battery in the truck and connect the leads to it, turn the ignition switch to "ON" (without trying to start the truck), open up the airbox and manually open the flap on the VAFM. If the logic is working, this should also start your fuel pump. If this doesn't work, then you can start troubleshooting the logic components one at a time. (As an alternative to the test in the last paragraph, after the battery is connected to the vehicle and the fuel pump connector is connected, you can select the key to "ON", and install a jumper wire between the "+B" and "FP" terminals in the DLC1 connector in the engine compartment. This bypasses the part of the logic containing the circuit opening relay and the VAFM, and only tests the fuses, EFI main relay and the fuel pump itself.)

MAINEiac

awesome,thank you very much. i did connect and test everything accordingly and the pump did not work,doesnt surprise me considering it was a carter put in maybe 3 years ago.