Concerned with cold lubricant causing backfire (6)
I believe the answer is:
recoil
'backfire' is the definition.
(I know that backfire can be written as recoil)
'concerned with cold lubricant' is the wordplay.
'concerned with' becomes 're' (re can mean regarding or about).
'cold' becomes 'C' (eg on taps).
'lubricant' becomes 'oil' (I've seen this before).
're'+'c'+'oil'='RECOIL'
'causing' is the link.
(Other definitions for recoil that I've seen before include "Stagger back" , "Start back like a gun on firing" , "Move or spring back suddenly, perhaps in disgust" , "Kick of gun" , "Flich or kick back" .)