1. Safety First: Park your Civic SI on a level surface, apply the parking brake, and turn off the engine. Disconnect the battery's negative terminal to avoid any electrical incidents during the process.
2. Raise the Vehicle: Use the floor jack to elevate the vehicle and securely place the safety stands under the car. Make sure it's stable before proceeding.
3. Locate the Fuel Pump Assembly: The fuel pump assembly is usually placed inside the fuel tank. It's typically accessible from the trunk or rear passenger seats. In the Civic SI, it's under a removable cover in the trunk.
4. Release Fuel Pressure: Before removing any fuel lines, relieve the fuel pressure in the system. There's a valve attached to the fuel rail, usually near the engine bay. Press the valve or disconnect a hose as specified by your vehicle's service manual.
5. Disconnect Fuel Lines: Underneath the access cover, you'll find the fuel lines connected to the fuel pump assembly. Use the fuel line disconnect tools or press the connectors and gently pry them off the fuel pump assembly. Expect a small amount of fuel to spill. Collect it in the drain pan.
6. Remove Fuel Pump Assembly: Use the 10 mm and 14 mm sockets with a ratchet to loosen and remove the bolts securing the fuel pump assembly to the fuel tank. You might need to use the flat-head screwdriver for support while removing the bolts. Carefully lift out the fuel pump assembly from the tank.
7. Remove Fuel Strainer and Seal: The old fuel strainer and seal should be replaced. Pry off the old ones using the needle-nose pliers. Save the 14 mm bolts to secure the new pump and seal.
8. Install New Fuel Strainer and Seal: Fit the new fuel strainer onto the fuel pump's inlet. Then, position the new seal onto the fuel pump assembly.
9. Reinstall Fuel Pump Assembly: Carefully lower the fuel pump assembly back into the fuel tank, aligning it properly with the seal and bolts. Start with hand-tightening the 14 mm bolts, then use the ratchet to secure them.
10. Reattach Fuel Lines: Reconnect the fuel lines by aligning the connectors with their respective ports and pressing until you hear a click.
11. Test Fuel System: Reconnect the battery's negative terminal and turn on the ignition to the "ON" position (without starting the engine). Listen for the fuel pump to prime and build up pressure. Check for any leaks around the assembly and fuel lines.
12. Start the Engine: Once assured there are no leaks, start the engine and let it run for a few minutes. Observe the fuel pressure gauge (if equipped) to ensure it's within the recommended range.
13. Test Drive: Take your Civic SI for a short drive to ensure that the fuel pump is functioning correctly. Address any issues immediately.
Replacing the fuel pump in a 1990 Honda Civic SI requires methodical steps and attention to detail. If you're unsure or uncomfortable performing this task, it's best to seek assistance from a qualified mechanic.
