Car part - tyre for Ford? (7)
I believe the answer is:
exhaust
'car part' is the definition.
(I've seen this before)
I cannot understand how the remainder of the clue works.
(Other definitions for exhaust that I've seen before include "Car part for carrying away gases - would make you tired" , "Pipe that carries engine fumes away" , "lower part of estate?" , "Sap - piped emission" , "Tube carrying off fumes from car engine" .)