Replacing The Fuel Pump In A 1999 Lincoln Continental

Changing the fuel pump on a 1999 Lincoln Continental can be a complex task. The fuel pump is located in the trunk, behind the carpet on the passenger side, and it is an in-tank electric fuel pump, which makes changing it a little difficult. However, with the right tools and safety precautions, it is possible to replace the fuel pump without completely removing the fuel tank. The process involves disconnecting the battery, relieving the fuel system pressure, siphoning the fuel, accessing the fuel tank and fuel pump assembly, cleaning the assembly area, and then installing the new fuel pump with a new O-ring seal. It is important to refer to a repair manual or seek assistance from a qualified technician to ensure the job is done correctly and safely.

Locating the fuel pump

To locate the fuel pump, follow these steps:

• Turn off the engine and locate the fuel pump fuse. Pull out the fuse and restart the engine to relieve the engine's pressure.
• Disconnect the negative battery terminal after the engine dies.
• Jack up the car and place jack stands underneath for support. Slide under the car and follow the fuel lines towards the fuel tank.
• Once you have located the fuel pump, you can proceed to unbolt it and replace it with a new one.

It is important to note that working on the fuel system can be dangerous, so it is recommended to park away from appliances with open flames, such as dryers and water heaters. Fuel vapors can easily ignite and cause serious injuries.

Removing the old pump

To remove the old pump from your 1999 Lincoln Continental, you will need to first remove the negative (black) battery cable with a wrench and loosen the fuel filler cap.

Next, locate the Schrader valve on the fuel supply manifold—the steel tube where the fuel injectors connect. Allow the engine to cool completely, then wrap a shop rag around the valve and depress the small valve stem with a small standard screwdriver to relieve the fuel system pressure, catching any fuel with the rag.

If your fuel tank is more than 1/4 full, siphon the fuel from the tank with a hand siphon pump into an approved fuel container. If your Continental model has an air suspension system, shut off the switch located on the side panel inside the trunk. You can consult your owner's manual for more information.

Now, raise the rear of your Continental with a floor jack and place a jack stand on each side under the frame for support. Block each front wheel with a wooden block. Unscrew the metal retainer holding the fuel filler hose to the tank's flange using a ratchet and socket set.

Place a wooden block on the floor jack's saddle and use the floor jack to support the tank. Unfasten the two straps that secure the tank to the vehicle with a ratchet, long ratchet extension, and socket. Swing the straps out of the way.

Lower the fuel tank partially with the floor jack. Depress the two tabs on the side of the fuel line fittings with your fingers and pull both lines off the fuel sending unit assembly. Unplug the electrical connector from the assembly as well.

Lower the fuel tank a few more inches to gain better access to the fuel-sending unit assembly. Clean the top of the assembly and the surrounding area with a shop rag to prevent dirt and grease from falling into the tank.

Finally, unfasten the bolts securing the assembly to the tank with a Phillips screwdriver and carefully lift the assembly, along with the O-ring seal between the assembly and the tank opening, out of the fuel tank.

You have now successfully removed the old fuel pump from your 1999 Lincoln Continental.

Installing the new pump

To install the new pump, first, place a new O-ring seal on a clean shop rag and spray it with white lithium grease. Then, place the O-ring seal on the fuel tank opening, with the greased side against the tank. This will help the seal stick to the opening as you install the fuel sending unit assembly.

Next, reinstall the fuel sending unit assembly into the fuel tank and tighten the retaining screws with a Phillips screwdriver. Plug in the electrical connector and reconnect the fuel lines.

Now, raise the fuel tank to its original position using the floor jack and secure it with the straps using the ratchet, long ratchet extension, and socket.

Finally, secure the metal retainer from the fuel filler hose to the tank's flange with the ratchet and socket.

Once the new pump is installed, lower your Continental with the floor jack and refill the tank with fuel using a small funnel. Check to ensure the tank is at least half full, then replace the fuel filler cap.

Check for fuel leaks at the fuel lines on the tank and turn on the air suspension system if your vehicle is equipped with one.

Finally, attach the negative (black) battery cable with the wrench. Turn the ignition switch on and off at least five times to pressurize the fuel system. Check again for fuel leaks. Start the engine, check for fuel leaks once more, then turn off the engine.

Testing the new pump

Testing the New Fuel Pump:

Step 1: Before starting the engine, turn the ignition switch on and off at least five times. This will help pressurize the fuel system and prepare it for testing. Make sure to check for any fuel leaks at the fuel lines on the tank during this process.

Step 2: Start the engine and carefully check again for any fuel leaks. It's important to ensure there are no leaks before proceeding. Once you're confident there are no leaks, turn off the engine.

Step 3: Locate the fuel pump in the fuel tank. Refer to your vehicle's manual or seek assistance from a mechanic if you're unsure where it is.

Step 4: Turn the key to the "run" position and listen carefully for any buzzing or humming noises coming from the fuel pump. A properly functioning fuel pump should produce an audible sound. If you don't hear anything, proceed to the next step.

Step 5: Set the amperage on a voltage meter and place the clamp on the positive wire connected to the fuel pump. This will allow you to measure the electrical current flowing to the pump.

Step 6: Start the vehicle and record the amperage reading from the voltage meter. Compare this reading to the manufacturer's specifications for your specific fuel pump model. The reading should be within the specified range.

Step 7: If the fuel pump did not turn on at all, proceed to disconnect the electrical connector on the pump. This could indicate a potential issue with the electrical connection or the pump itself.

Step 8: Set the DC volts on the meter and place the positive meter lead on the positive wire terminal in the connector. Place the negative meter lead on the negative wire terminal.

Step 9: Turn the key to the "run" position again and observe the voltage reading. If the voltage reading is the same as the battery voltage, it indicates that the fuel pump has failed and needs to be replaced.

Step 10: If the pump is functioning properly, perform a fuel pressure test. Purchase a fuel pressure gauge from an auto parts store. These are usually affordable and can be borrowed from some machine or auto shops.

Step 11: Locate the fuel pump test point, which is usually near the fuel injectors or the fuel rail. Attach the pressure gauge to the test fitting or port. Refer to your owner's manual for specific instructions, as the location may vary depending on your vehicle.

Step 12: Warm up the engine slightly and then check the fuel pressure at idle speed and at the rated speed listed in your pump specifications. If the pressure is below specifications or doesn't increase when you rev the engine, it could indicate a problem with the fuel pump or a clogged fuel filter.

Step 13: If the pressure matches the specifications and increases with engine speed, your new fuel pump is likely functioning correctly. However, if you suspect any issues or unusual behavior, consult a professional mechanic for further diagnosis.

Remember to prioritize safety during the testing process. Keep a fire extinguisher nearby and wear appropriate protective gear, including safety glasses, when working on the fuel system.

Safety precautions

Changing the fuel pump on a 1999 Lincoln Continental can be a complex and potentially dangerous task. Here are some safety precautions to follow:

Work in a Well-Ventilated Area: Fuel vapours can be dangerous, so it is important to work in a well-ventilated area, away from any appliances with open flames such as dryers or water heaters.

Allow the Engine to Cool: Before beginning any work on the fuel pump, allow the engine to cool completely. A hot engine can cause burns and increase the risk of fire.

Disconnect the Battery: Before starting, disconnect the negative (black) battery cable with a wrench. This will prevent any accidental electrical shorts or sparks that could cause an explosion.

Relieve Fuel System Pressure: Wrap a shop rag around the Schrader valve on the fuel supply manifold and depress the small valve stem with a small standard screwdriver to relieve the fuel system pressure. Be careful as fuel may squirt out.

Siphon the Fuel: If your fuel tank is more than 1/4 full, siphon the fuel into an approved fuel container using a hand siphon pump. Working with a partially empty fuel tank reduces the risk of spills and fire.

Secure the Vehicle: Use a floor jack to raise the rear of the vehicle and place jack stands on each side under the frame for support. Block each front wheel with a wooden block to prevent accidental movement.

Use Proper Tools: Ensure you have the correct tools for the job, such as a ratchet and socket set, long ratchet extension, Phillips screwdriver, standard screwdriver, and white lithium grease. Using the wrong tools can damage the vehicle or cause injury.

Prevent Dirt and Debris: When lowering the fuel tank, clean the top of the fuel-sending unit assembly and surrounding area with a shop rag to prevent dirt and grease from falling into the tank.

Be Prepared for Spills: Keep absorbent rags and other cleanup materials on hand in case of fuel spills.

Follow Instructions: If you are unsure about any steps, refer to a repair manual or seek advice from a qualified mechanic. Improper installation or reinstallation of the fuel pump can lead to leaks, electrical issues, or other problems.

Safety Gear: Wear safety goggles and gloves to protect your eyes and hands during the process.

Frequently asked questions