I have a 1998 Mercury Sable 3.0 liter Duratec engine. Runs great until when it stopped suddenly. I just filled the cars gas tank and drove one block and it quit. After checking it out, I have spark at the plugs but no fuel at the fuel rail. The 20A fuse in the power dist. box checks out, and I swapped the relays as suggested in the Hanes repair manual and still no fuel. I can't hear the pump come on with the ignition, even if I take the gas cap off and listen at the tank. Battery has been replaced and connections cleaned. I have been having problems over the past month with the battery losing power if the car sat for three or four days. The inertia switch in the trunk is good, but for some reason, I only have 7 volts coming into the switch, on the green/yellow striped wire. When I put 12 volts to the pink/black striped wiring leaving the switch (to the pump?) it sparks like I'm touching ground....any ideas??? I'm stumped!!