Nissan Micra - Throttle body - BK Boys

Hi all, we are working on a micra Inicia 2006. Ran a diagnostic on it and it says there is an issue with the airflow via the throttle body. We have made enquiries to replace the sensor, but people say you have to replace the whole throttle body. Why is this so when the sensor (faulty) is detachable?. Has anyone else come across ths issue?

Cheers Keith

Nissan Micra - Throttle body - Avant

Moved to Technical.