The Cadillac Eldorado had eight generations of designs during its production between the 1950s and 2002. The modern Eldorado came with four different engine sizes: 4.1-liter, 4.5-liter, 4.6-liter and 4.9-liter. Each model features an electronic fuel pump. The electronic fuel pump sits in the fuel tank. It filters and pumps fuel to the fuel injectors in the engine. If the pump is faulty, the Eldorado may not start or may stall while you're driving.
Open the hood. Remove the negative battery terminal nut. Pull off the negative cable from the battery.
Open the gas cap. Insert the siphon into the gas filler hose. Lower the siphon until it reaches below the gas line in the tank. Pump the gas out of the tank into spare gas cans. This step makes it much easier and safer to remove the fuel tank.
Engage the emergency parking brake. Raise the rear of the Eldorado with a car jack. Set two jack stands underneath the Eldorado to stabilize it while you work below the car.
Put on your latex gloves. Loosen the securing rings that hold the ventilation hose and filler hose to the fuel tank with your screwdriver. Pull off the rings. Pull the hoses off of the fuel tank joints.
Set the floor jack below the fuel tank. Remove the front strap holding the fuel tank in place with a socket wrench. Pry the fuel tank away from the frame rail with a screwdriver to set the loosened end of it on the floor jack.
Locate the fuel pump above the revealed top of the fuel tank. Remove the return fuel hose, emissions evaporation hose and wiring connectors from the pump. Disconnect the electrical connectors by pressing in on the side tabs. Slip the quick-disconnect tool around the fitting on one of the hoses. Press the quick-disconnect tool together. Pull off the hose. Repeat this process for the other hose.
Remove the other strap holding the tank in place. Push the floor jack out from underneath the Eldorado with the tank on top of it.
Clean the top of the tank with the acetone-based cleaning agent and some rags. Dislodge the locking ring tabs around the fuel pump from the slots in the fuel tank by hitting them with a brass punch and mallet until they are loose enough to pull out. Lift off the ring. Pull up on the fuel pump slightly, enough to reach into the opening. Press away on the tabs on the fuel tank to release the pump from the tank. Navigate the fuel pump out of the opening on the tank. Remove the fuel pump gasket.
Smear the new gasket from the fuel pump kit with fresh motor oil. Place it over the opening to the tank. Insert the new fuel pump into the tank. Seat it all the way to the bottom of the tank. Listen for the tabs on the tank to catch on the slots of the fuel pump, securing it in place. Secure the locking ring around the fuel pump.
Reinstall the fuel tank below the Eldorado. Connect all of the hoses and electrical connectors you removed earlier.
Refill the fuel pump with the fuel you siphoned out. Reconnect the engine bay battery. Turn on the Eldorado. Turn off the Eldorado after three seconds. Turn the Eldorado on and off like this five or six more times until the engine cranks. This indicates that fuel has been pumped through the system. Check that there are no fuel leaks below the Eldorado. Turn off the car if there is a leak. Refit any leaking joints. Turn the Cadillac back on and check again. Lower the vehicle to the ground if there are no leaks.
