Favourite car working (6)

I believe the answer is:

minion

'favourite' is the definition.

'car working' is the wordplay.
'car' becomes 'mini' (Mini Cooper**).
'working' becomes 'on'.
'mini'+'on'='MINION'

(Other definitions for minion that I've seen before include "Servile follower" , "Servile dependant" , "Flunky" , "flunkey" , "Fawning servant" .)

I've seen this clue in The Telegraph.

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