1. Locate the fuel tank. On an Alfa Romeo 156, the fuel tank is located under the rear seat.
2. Remove the access panel. There should be a small access panel on the underside of the rear seat. Remove this panel to access the fuel pump.
3. Locate the fuel pump. The fuel pump is a cylindrical-shaped object with two fuel lines attached to it. It is usually located near the bottom of the fuel tank.
4. Remove the fuel lines. Use a wrench to loosen the fuel lines that are attached to the fuel pump. Be careful not to spill any fuel.
5. Remove the fuel pump mounting bolts. There are usually four bolts that hold the fuel pump in place. Use a wrench to loosen these bolts and remove the fuel pump.
6. Inspect the fuel pump. Once you have removed the fuel pump, inspect it for any damage. If the fuel pump is damaged, it will need to be replaced.
7. Reinstall the fuel pump. If the fuel pump is not damaged, reinstall it by reversing the steps above.