Voltage to the pump on gray circuit 120 comes from the fuel pump relay, and ECM B fuse, both of which are in the underhood fuse block. The fuel pump relay is controlled by the PCM. It controls the power side, and the ground is hard wire to G102, which is on the rear of the passenger side cylinder head, near the distributor. Check the ECM B fuse, it is hot at all times. You should see power on one leg of the relay at all times, and another leg should be hot at key up for a couple seconds, unless you are cranking, then it should be hot while cranking. You are only going to have voltage present at the pump connector for the same time that the relay is on. If you have not checked it while cranking, you should. If it changes, and you do have voltage, it is potentially a faulty pump. You can also listen for the fuel pump relay clicking, both at key on, and while cranking. This would be an indication that it is being controlled. Swap the relay with another in the fuse block as well, it could be a faulty relay.
Apr 6, 2010 at 10:38 AM
