Drain the fuel tank and disconnect the negative cable from the battery, ensuring to read the battery disconnection cautions beforehand. Remove the rear seat to access the fuel pump and Fuel Level Sensor, then disconnect the harness connector for the fuel pump and Fuel Level Sensor by sliding the lock to release it. Cut the hose clamp and disconnect the hose. Use BMW special tool 16 1 020 to remove the locking ring on the fuel tank cover, then remove the cover and slowly withdraw the Fuel Level Sensor to expose the spiral hose. Carefully remove the Fuel Level Sensor and fuel pump assembly from the tank, allowing fuel to drain off while turning the unit in different directions to avoid damaging the sensor. Take care as the Fuel Level Sensor is vulnerable; gently tilt the front of the cover upwards for removal and avoid bending the sensor arm. Installation is the reverse of removal, ensuring to use a new sealing gasket and insert it into the tank opening, guide the Fuel Level Sensor into the opening, align the sensor lug with the notch in the fuel tank, listen for the notch on the locking ring to engage the tooth on the tank, and tighten the locking ring to the specified torque. Ensure the fuel line connections point in the same direction as before, reconnect the harness connector and fuel hose using a new hose clamp, add fuel, and check for leaks by running the engine. Finally, install the access cover, and ensure there is at least 5 liters (1.5 gallons) of fuel in the tank before starting the engine to prevent damage to the fuel pump. It is also common practice to replace the fuel filter when the fuel pump is replaced.
