I have an 87 F150, 4.9L, EFI (Calif model), 3-spd with O/D and two tanks. I have had both in-tank fuel pumps replaced and selector valve (6-port) removed and cleaned. Mechanic said he did continuity check on switch and that the switch was OK. Same mechanic who did the in-tank pump/filter work and removal and cleaning of the selector valve said both tank fuel pumps "clicked" when selector switch was moved from Front to Rear, etc, and gave him the impression that the switch was selecting each tank correctly as selected.

Problem: Only the Rear tank is in service, regardless of switch position. Gas gauge reflects normal movement when in the Rear position, but does not move when in the Front tank position. Also, no gas is used from Front tank. It remains full.

Any help would be greatly appreciated. Thanks.