2006 acura Tl AC not cold enough, can I use the do it your self can to add more Ac gas

What is your question?

I just purchased an Acura 2006 TL from Orig owner. it has 166k. car is in pristine condition and mechanically all is fine. Ac compressor was changed at 140 K , the problem AC not cold enough but vents and airflow is fine. Can I use the do it your self can to add some more AC GAS. The newer cars need the diagnostic to be done first and its expensive. but becuase this is 2006 can I do it with the can without causing damage.

What makes this problem better or worse?

hotter temp takes longer to cool

How long has your 2006 Acura TL had this problem?

1 week