Economize to a fault (5)
I believe the answer is:
skimp
'economize to a fault' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for skimp that I've seen before include "Subsist on very little" , "Be parsimonious, stint" , "Work hastily" , "Spend not enough time and care on (job)" , "Expend less in an attempt to economise" .)