hi stephen i wasent as clever as philpo dropped two spanners trying to get airflow sensor off just as easy to whip off the front cowl you can also retrieve your lost spanners sprays are available to clean the sensor not wd40 stick it back on before replacing the cowl it might just be dirty otherwise its about eighty quid for a new pattern sensor or about hunderd and sixty for bmw x5 original dont forget to clean your fault code hope this helps
