Here's a general outline; specifics may vary slightly depending on your exact engine (4.9L or 4.5L):
1. Safety First:
* Disconnect the negative battery terminal. This prevents accidental sparks that could ignite fuel vapors.
* Work in a well-ventilated area. Fuel vapors are highly flammable.
* Wear safety glasses and gloves.
* Have a fire extinguisher readily available.
2. Preparation:
* Locate the fuel pump access panel. This is usually located in the trunk, under the carpeting. You may need to remove some trim pieces to access it. Consult your repair manual for the precise location.
* Gather your tools: You'll need sockets, wrenches (including a fuel line disconnect tool if possible, otherwise careful use of pliers and patience), screwdrivers, jack stands (if you're lowering the tank), a fuel pump removal tool (often specialized), rags, and possibly a fuel pressure gauge (to ensure proper pressure after installation). A repair manual is highly recommended.
3. Fuel System Depressurization:
* Start the engine and let it run until it stalls. This will use up the fuel pressure in the system.
* Double-check the pressure. If you have a fuel pressure gauge, it's best to use it to verify that the pressure is zero.
4. Accessing the Fuel Pump:
* This is the most variable part of the process. Some DeVille models require dropping the fuel tank (a significant undertaking), while others have an access panel that allows you to reach the pump without removing the tank. Your repair manual will be your best guide here.
* If dropping the tank is necessary: You'll need to support the tank safely, disconnect the fuel lines, the electrical connector, and any other connected components. Be extremely careful with the fuel lines to avoid spills.
5. Removing the Fuel Pump:
* Disconnect the electrical connector to the fuel pump.
* Disconnect the fuel lines. Use the fuel line disconnect tool if you have one. Otherwise, carefully pry the lines apart with pliers. Be prepared for some fuel spillage – have rags ready.
* Remove the retaining ring or cover holding the fuel pump assembly in place. This often requires a special tool.
* Carefully lift the fuel pump assembly out of the tank.
6. Installing the New Fuel Pump:
* Reverse the removal process: Carefully install the new fuel pump assembly, making sure the o-rings are properly seated.
* Reconnect the fuel lines and the electrical connector.
* Reconnect the retaining ring or cover.
* Lower the fuel tank (if applicable).
* Reconnect the fuel tank straps and other components.
7. Reassembly and Testing:
* Carefully replace all access panels and trim pieces.
* Reconnect the negative battery terminal.
* Start the engine and listen for any unusual noises.
* Check for leaks.
* Verify that the car runs normally.
Important Notes:
* Consult a repair manual specific to your 1992 Cadillac DeVille. This is crucial for accurate instructions and torque specifications. A Haynes or Chilton manual are good options.
* If you're uncomfortable with any part of this process, take your car to a qualified mechanic. Improperly working with the fuel system can be dangerous.
* Dispose of old fuel and components properly. Follow local regulations for hazardous waste disposal.
This is a general guide. The exact procedure will depend on your specific vehicle. Always prioritize safety and refer to your vehicle's repair manual for detailed and accurate instructions.
