Your 1993 Jeep Grand Cherokee uses an electric in-tank fuel pump. However, you do not need to lower the tank to replace a failed pump, which makes it relatively easy to replace. Still, you want to make sure the O-ring under the sending unit assembly, which contains the fuel pump, seals properly. It is not uncommon for this seal to move as you replace the assembly, causing fuel leaks. Paying attention to detail, you can install the new pump in about 90 minutes using a few simple tools.
Detach the ground battery cable (black) using a wrench and loosen the fuel filler cap.
Unscrew the cap from the pressure test port on the fuel rail. The test port is similar to the air valve on your Cherokee tires and is located on the fuel pipe leading to the fuel injectors on the top area of the engine.
Cover the test port with a shop towel and depress the valve with a small flat head screwdriver. Catch the squirt of fuel with the shop towel then replace the cap on the test port.
Siphon the fuel from the fuel tank into an approved container using a hand siphon pump.
Lift the rear of your Jeep using a floor jack. Place a jack stand on each side for support and lower the vehicle.
Loosen the clamps holding the two fuel hoses to the fuel sending unit fittings on the fuel tank using a flat head screwdriver. If necessary, label the hoses before disconnecting them.
Wrap a shop towel around either one of the hoses at the fuel sending unit then pull the hose off the fitting at the fuel sending unit. Use the shop towel to absorb any residual fuel in the hose.
Unplug the wiring harness electrical connector from the fuel sending unit.
Rotate the retaining locking ring on the fuel sending unit counterclockwise using a brass punch and hammer until the ring is free.
Lift the fuel sending unit off the fuel tank and remove the O-ring seal under the unit’s flange.
Remove the fuel sending unit from the Jeep and detach the fuel pump wires from the unit.
Loosen the pump hose clamp at the fuel sending unit using the flat head screwdriver then detach the hose from the unit.
Unscrew the top bracket nut holding the pump to the fuel sending unit then remove the fuel pump from the unit using a ratchet and socket.
Place the new fuel pump in position in the fuel sending unit then tighten the top bracket nut using the ratchet and socket.
Connect the pump hose to the fuel sending unit and tighten the clamp using the flat head screwdriver.
Attach the fuel pump wires to the unit.
Place a new O-ring seal on the fuel tank opening.
Install the fuel sending unit in the tank and rotate the retaining locking ring clockwise with the brass punch and hammer until the ring hits the stops.
Plug the wiring harness electrical connector to the fuel sending unit.
Attach the fuel hoses to the fuel sending unit and tighten the clamps using the flat head screwdriver.
Lower the Jeep with the floor jack.
Refill the fuel tank.
Reattach the ground battery cable (black) using the wrench then retighten the fuel filler cap.
Start the engine and check for fuel leaks at the tank.
