How to Change a Fuel Pump on a 1994 Cadillac DeVille

The fuel pump on a 1994 Cadillac DeVille is mounted in the gas tank. This pump is responsible for getting gasoline from the tank to the engine. Should the pump fail or start to fail, then the engine will first have trouble running before failing completely in turn. Replacing the fuel pump takes at least an hour, but does not require any special tools or equipment.

Things You'll Need

  • Wheel chocks
  • Jack
  • Jack stands
  • 3/8-inch ratchet, extension and socket set
  • Brass hammer
  • Brass drift
  • Flathead screwdriver
  • Replacement fuel pump
  • Park the DeVille on a level surface and put the wheel chocks around the front wheels. Lift the rear of the Cadillac with the jack and put jack stands under the rear axle.

  • Place the jack under the gas tank. Unbolt the gas tank straps from the chassis with the 3/8-inch ratchet, extension and sockets. Lower the jack down until you can access the top of the tank. Crawl under the Cadillac and locate the gas tank, which is near the rear axle. Remove the hose clamps holding the fuel lines to the tank and the fuel filler neck to the tank using the flathead screwdriver. Unplug the wiring to the fuel pump with your hands. Then lower the tank the rest of the way and pull the tank out from under the Cadillac.

  • Turn the locking ring on the top of the fuel tank sending unit and fuel pump assembly using the brass drift and brass hammer. Lift the sending unit/fuel pump assembly straight up out of the tank. Locate the fuel pump, which is bottom of the tank. Pull the pump straight up out of the assembly and move it to the side.

  • Pull off the strainer from the fuel pump with your hands and install it on the replacement fuel pump. Install the replacement fuel pump onto the assembly with your hands. Install the replacement fuel pump into the tank and use the brass drift and brass hammer to install the locking ring and secure the assembly into the tank.

  • Lift the tank up into the chassis and reconnect the fuel lines and electrical connections to the tank using the flathead screwdriver. Bolt the tank mounting straps onto the chassis with the 3/8-inch ratchet, extension and sockets. Lower the Cadillac off of the jack stands using the jack.