Skinflint getting faultless service on the motorway (5)
I believe the answer is:
miser
'skinflint' is the definition.
(synonyms)
'faultless service on the motorway' is the wordplay.
'faultless service' becomes 'iser' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'on' means one lot of letters go next to another.
'the motorway' becomes 'M' (as in motorway names - Mi, Mr etc).
'iser' put after 'm' is 'MISER'.
'getting' is the link.
Can you help me to learn more?
(Other definitions for miser that I've seen before include "Penny-pincher" , "Pinchpenny" , "Money-grubber" , "auger" , "Curmudgeon" .)