Right of car is illegally positioned (7)
I believe the answer is:
offside
I believe this is a double definition.
'right of car' is the first definition.
(side of a vehicle furthest from the pavement)
'illegally positioned' is the second definition.
(football term)
'is' acts as a link.
(Other definitions for offside that I've seen before include "Illegal state in football" , "Illegal football position between the ball and opponents' goal" , "Illegally ahead of the ball in soccer" , "in no position to score goal" , "(in the UK) a vehicle's right" .)