The old man with something wrong pays quick visit (4,2)
I believe the answer is:
pops in
'pays quick visit' is the definition.
I can't judge whether this defines the answer.
'the old man with something wrong' is the wordplay.
'the old man' becomes 'pop' (both can mean someone's father).
'with' is a charade indicator (letters next to each other).
'something wrong' becomes 'sin' (something morally wrong).
'pop'+'sin'='POPS IN'
Can you help me to learn more?
(Another definition for pops in that I've seen is " Makes brief visit".)