Popular car practically ran without noise (9)
I believe the answer is:
inaudible
'without noise' is the definition.
'popular car practically ran' is the wordplay.
'popular' becomes 'in'.
'car' becomes 'audi' (audi is a german car brand).
'practically' means to remove the last letter.
'ran' becomes 'bled' ('bleed' can be a synonym of 'run').
'bled' with its final letter taken away is 'ble'.
'in'+'audi'+'ble'='INAUDIBLE'
(Other definitions for inaudible that I've seen before include "Impossible to hear" , "Cannot be heard" , "Unable to be heard" , "impossible to grasp" , "Not aurally detectible" .)