Vehicle gets through blustery rain - sheer delight! (7)
I believe the answer is:
nirvana
'sheer delight' is the definition.
'vehicle gets through blustery rain' is the wordplay.
'vehicle' becomes 'van' (van is a kind of vehicle).
'gets through' is an insertion indicator.
'blustery' is an anagram indicator.
'rain' anagrammed gives 'nira'.
'van' placed into 'nira' is 'NIRVANA'.
(Other definitions for nirvana that I've seen before include "State of ideal happiness" , "Iran van (anag) - blissful state!" , "Eastern place or state of bliss" , "Buddhist paradise or hereafter" , "Buddhist state of bliss; enlightenment" .)