Here's a general outline of the process. Specific steps may vary slightly depending on the exact engine and trim level:
1. Safety First:
* Disconnect the negative battery cable. This is paramount to prevent accidental ignition.
* Release fuel pressure. This is critical. You'll likely need to crank the engine several times until it sputters and dies (after disconnecting the battery, of course), as there's no manual fuel pressure release valve on most systems from that era. Alternatively, a fuel pressure gauge and release tool can assist.
* Work in a well-ventilated area. Gasoline fumes are flammable and dangerous.
* Use appropriate safety glasses and gloves.
2. Access the Fuel Pump:
* Locate the fuel pump access panel. This is usually located under the rear seat (in the trunk area for some models) or sometimes under the vehicle, near the fuel tank. Consult your vehicle's repair manual to identify the exact location. You may need to remove parts of the interior trim or underbody shields.
* Remove the access panel. This may involve unbolting or unclipping it.
3. Remove the Fuel Pump:
* Disconnect the electrical connector. This connector supplies power to the fuel pump.
* Disconnect the fuel lines. You'll need fuel line disconnect tools or pliers to carefully separate the lines from the pump. Have rags ready to absorb any spilled fuel. Mark which line goes where to avoid confusion during reassembly.
* Remove the fuel pump retaining ring or bolts. This will vary depending on your specific model. You may need specialized tools for this.
* Carefully lift out the fuel pump assembly. The assembly typically includes the pump, sending unit (fuel level sensor), and strainer.
4. Install the New Fuel Pump:
* Carefully inspect the new fuel pump. Make sure it matches your old one.
* Reverse the removal process. Install the new fuel pump assembly, ensuring a snug fit.
* Reconnect the fuel lines. Ensure the lines are securely attached and there are no leaks.
* Reconnect the electrical connector.
* Reinstall the retaining ring or bolts.
* Reinstall the access panel.
5. Final Steps:
* Reconnect the negative battery cable.
* Check for leaks. Inspect all fuel lines and connections for leaks.
* Start the engine. Listen for any unusual noises and check for any fuel leaks.
* Check the fuel gauge. Ensure the fuel level reading is accurate.
Important Considerations:
* Repair Manual: Obtaining a repair manual specific to your 1991 Buick Century is highly recommended. It will provide detailed diagrams, torque specifications, and step-by-step instructions.
* Fuel Pump Replacement Kit: Often, a fuel pump replacement kit is sold which includes new fuel filters and seals, making the job easier and ensuring a better seal.
* Professional Help: If you're uncomfortable performing this repair yourself, it's best to take your vehicle to a qualified mechanic. Working with fuel systems requires caution and expertise.
This is a general guide, and the exact procedure may vary. Always consult a repair manual for your specific vehicle model before attempting this repair. Improperly performing this task can lead to fuel leaks, fire hazards, or damage to your vehicle. Safety should be your top priority.
