Here's a general outline. Consult a repair manual specific to your 1995 Chevrolet Impala for detailed instructions and diagrams. These instructions are for guidance only and may not be perfectly accurate for your specific vehicle. Improper procedure could lead to injury or damage.
1. Preparation:
* Safety First: Disconnect the negative battery cable. Allow the fuel system pressure to fully depressurize. This is crucial to prevent fuel spraying. You may need to start the engine and let it run until it stalls (after disconnecting the fuel pump relay or fuse) to use up the residual pressure. Never work near an open flame or sparks.
* Gather Tools: You'll need jack stands, a jack, various sockets and wrenches (metric), screwdrivers (Phillips and flathead), fuel line disconnect tools, a fuel pump removal tool (often a specialized tool to prevent damage to the retaining ring), safety glasses, gloves, rags, and possibly a new fuel filter (often a good idea to replace at the same time). A torque wrench is highly recommended.
* Obtain Replacement Parts: Ensure you have the correct fuel pump assembly for your Impala's engine. Note that some models may require specific pump assemblies and you must cross-reference your vehicle identification number (VIN) against parts diagrams to confirm.
* Locate the Fuel Pump: On most 1995 Impalas, the fuel pump is located inside the fuel tank, accessed from underneath the vehicle.
2. Accessing the Fuel Pump:
* Lower the Fuel Tank: This usually involves lowering the fuel tank. You'll need to support the tank with jack stands once it's lowered. Consult your repair manual for the specific procedure, as it involves disconnecting fuel lines, electrical connectors, and possibly the fuel tank straps or sending unit. Be extremely careful not to damage the fuel lines or tank itself.
* Remove the Fuel Pump Access Cover: Once the tank is lowered, you'll find a cover (access plate) that protects the fuel pump. This might require removal of some retaining screws or clips.
3. Fuel Pump Replacement:
* Disconnect Electrical Connections: Carefully disconnect the electrical connectors from the fuel pump and the fuel level sender unit. Take pictures to aid in reassembly.
* Disconnect Fuel Lines: Using appropriate fuel line disconnect tools, carefully disconnect the fuel supply and return lines. Have rags ready to absorb any spilled fuel.
* Remove the Fuel Pump: Use the fuel pump removal tool to carefully remove the fuel pump assembly from the tank. This retaining ring can be difficult to remove without the proper tool.
* Install New Fuel Pump: Carefully install the new fuel pump assembly, making sure the o-ring is in place to prevent leaks. Use the removal tool in reverse to secure the new pump.
* Reconnect Fuel Lines and Electrical Connections: Carefully reconnect the fuel lines and electrical connectors, ensuring a tight and secure fit.
4. Reassembly:
* Raise the Fuel Tank: Carefully raise the fuel tank back into its position and secure it with the retaining straps or brackets.
* Reconnect Fuel Lines and Electrical Connections (double-check): Reconnect any lines that were disconnected. Double-check *everything*.
* Reconnect the Battery: Reconnect the negative battery cable.
* Prime the Fuel System (if necessary): Some vehicles require priming the fuel system after a fuel pump replacement. Your repair manual will detail this process. It might involve turning the ignition key on and off several times before cranking the engine.
* Check for Leaks: Carefully inspect for any fuel leaks.
5. Post-Installation:
* Start the Engine: Start the engine and check for proper operation. Listen for unusual noises coming from the fuel pump.
* Test Drive: Take the car for a test drive to ensure the fuel pump is functioning correctly.
* Check for Error Codes: Use an OBD-II scanner to check for any diagnostic trouble codes.
Disclaimer: This is a simplified overview. Always refer to a repair manual specific to your 1995 Chevrolet Impala before attempting this repair. Improper installation can lead to serious damage, injury, or even fire. If you're not comfortable performing this repair yourself, take it to a qualified mechanic.
