Safety First:
* Disconnect the negative battery terminal. This prevents sparks that could ignite fuel vapors.
* Work in a well-ventilated area. Fuel vapors are highly flammable.
* Use appropriate safety glasses and gloves.
* Obtain a fuel pump replacement kit. This usually includes the pump, filter, and gasket(s).
General Steps:
1. Vehicle Preparation: Park on a level surface, engage the parking brake, and chock the wheels.
2. Fuel System Depressurization: You need to relieve pressure in the fuel system. This usually involves disconnecting the fuel pump relay (consult your repair manual for its location) and running the engine until it stalls. Then, wait several minutes to allow pressure to fully dissipate. Double-check that there is no pressure before proceeding.
3. Access the Fuel Pump: This usually involves lowering the fuel tank. The exact procedure varies depending on the Sunfire's specific configuration (e.g., sedan, coupe), but generally involves:
* Removing the rear seat bottom cushion: Accessing the fuel tank often requires this.
* Locating the fuel tank access panel: This might be a small cover or require removing part of the inner rear wheel well trim.
* Disconnecting the fuel lines: This is critical and requires careful attention. Have appropriate containers to collect any spilled fuel. Note how the lines are connected for easy reassembly. You may need special fuel line disconnect tools.
* Disconnecting the electrical connector: Unplug the fuel pump electrical connector.
* Detaching the fuel pump assembly: This is usually secured by a retaining ring or clamp. This may require some force.
4. Fuel Pump Replacement:
* Remove the old fuel pump assembly: Carefully remove the assembly from the tank.
* Inspect the fuel tank: Check for any damage or debris inside.
* Install the new fuel pump assembly: Carefully install the new assembly, ensuring a proper seal.
* Replace the retaining ring or clamp.
5. Reassembly:
* Reconnect the fuel lines: Ensure a tight and secure connection.
* Reconnect the electrical connector: Make sure it clicks into place.
* Reinstall the fuel tank access panel.
* Reinstall the rear seat bottom cushion.
6. System Re-pressurization and Testing: Reconnect the fuel pump relay. Start the engine and check for leaks. Listen for the fuel pump to prime. Let the engine run for a few minutes to ensure proper operation. Monitor for leaks and unusual noises.
Important Considerations:
* Repair Manual: A repair manual specific to your 1996 Pontiac Sunfire is absolutely essential. It will provide detailed instructions, diagrams, torque specifications, and other crucial information.
* Tools: You will need a variety of tools, including sockets, wrenches, screwdrivers, possibly fuel line disconnect tools, and possibly a fuel pump removal tool.
* Fuel Safety: Fuel is extremely flammable. Take all necessary precautions to prevent fires.
* Professional Help: If you are not comfortable with this type of repair, consider taking your vehicle to a qualified mechanic.
This is a simplified overview. Improperly replacing a fuel pump can lead to serious consequences, including fire and injury. Always refer to a reliable repair manual for your specific vehicle before attempting this repair. If you are unsure about any step, consult a professional mechanic.
