Sleep with dandy in car on the way back (4,3)
I believe the answer is:
drop off
'sleep' is the definition.
(thesaurus)
'dandy in car on the way back' is the wordplay.
'dandy' becomes 'fop' (synonyms).
'in' is an insertion indicator.
'car' becomes 'ford' (Ford is a make of car).
'on the way back' says the letters should be written in reverse.
'fop' inserted within 'ford' is 'ffopord'.
'ffopord' reversed gives 'DROP-OFF'.
'with' is the link.
(Other definitions for drop off that I've seen before include "Decline, decrease" , "Fall < or crash" , "delivery of goods" , "Fall asleep" .)