Here's a general outline. This is not a substitute for a detailed repair manual specific to your vehicle's year and engine. Consult a repair manual (like a Haynes or Chilton manual) for precise instructions, torque specifications, and diagrams specific to your car's model. Improper installation can lead to serious damage or injury.
1. Preparation:
* Safety First: Disconnect the negative battery terminal.
* Gather Tools: You'll need jack stands, a jack, wrenches (various sizes), sockets, a fuel line disconnect tool, possibly a fuel pump pliers, safety glasses, gloves, rags, and potentially a fuel pressure gauge.
* Obtain Parts: Get a new fuel pump, fuel filter (recommended replacement), and any necessary gaskets or o-rings. Ensure the new pump is the correct one for your engine.
* Locate the Fuel Pump: On most vehicles of this era, the fuel pump is located within the fuel tank. Access usually requires dropping the fuel tank.
2. Fuel Tank Removal:
* Drain the Fuel Tank: This is crucial to prevent spills. Use a siphon pump to carefully drain the fuel into a suitable container.
* Disconnect Fuel Lines: Carefully disconnect the fuel lines using the proper fuel line disconnect tool. Be prepared for some fuel spillage. Have rags ready to absorb any fuel.
* Disconnect Electrical Connections: Disconnect the electrical connector(s) to the fuel pump.
* Release Tank Straps: Locate the straps or mounting bolts securing the fuel tank. There are typically several. Carefully remove them.
* Lower the Fuel Tank: Carefully lower the fuel tank. It's heavy and full of fumes, so use jack stands for support and take your time. This may require removing exhaust components or other parts for clearance. Consult your repair manual for specific steps.
3. Fuel Pump Replacement:
* Access the Fuel Pump: Once the tank is lowered (or sometimes partially lowered, depending on design), you should have access to the fuel pump assembly. This usually involves removing an access panel or cover on the top of the tank.
* Remove the Old Fuel Pump: Carefully remove the old fuel pump assembly. This often involves removing retaining rings, clips, or bolts. Pay close attention to the assembly, take photos if needed, so you can reassemble the new pump correctly.
* Install the New Fuel Pump: Install the new fuel pump assembly, following the reverse procedure of removal. Make sure everything is seated properly and all gaskets are in place.
* Reinstall Fuel Tank: Carefully raise the fuel tank back into position and re-secure it. Reconnect the fuel lines and electrical connections.
4. Reassembly and Testing:
* Reconnect Fuel Lines and Electrical Connections: Carefully reconnect the fuel lines and electrical connectors, ensuring a secure connection.
* Raise Fuel Tank: Securely raise and mount the fuel tank.
* Reconnect Battery: Reconnect the negative battery terminal.
* Check for Leaks: Carefully inspect all connections for leaks.
* Start the Engine: Start the engine and listen for unusual noises. Check for fuel leaks.
Crucial Considerations:
* Fuel Pressure: You might want to check the fuel pressure after the replacement to ensure the new pump is functioning correctly. A fuel pressure gauge is required for this.
* Repair Manual: This is absolutely critical. The steps above are very general. A specific repair manual will guide you through the precise steps for your 1990 Oldsmobile Toronado Trofeo. Improper installation could lead to serious damage to your vehicle or injury to yourself.
* Professional Help: If you're not comfortable performing this repair yourself, take your vehicle to a qualified mechanic. This is a potentially hazardous job if not done correctly.
Remember, this is a simplified overview. Always consult a repair manual for your specific vehicle model before attempting this repair. Safety should be your top priority.
