Factory recommends 5w-30 grade oil.
Read the manual the info is in there!
The 2009 Acura TSX runs on premium unleaded (recommended).
Use exactly what Acura recommends and nothing else.
For a 2009 Acura TSX, it's recommended to use 5W-20 motor oil that meets API (American Petroleum Institute) standards. You can choose between conventional, synthetic blend, or full synthetic oil, with full synthetic offering better performance and protection, especially in extreme temperatures. Always check the owner's manual for specific recommendations and specifications.
The 2008 Acura TSX runs on premium unleaded (recommended).
The 2005 Acura TSX runs on premium unleaded (required).
The 2012 Acura TSX runs on premium unleaded (recommended).
The 2006 Acura TSX runs on premium unleaded (required).
The 2013 Acura TSX runs on premium unleaded (recommended).
The 2007 Acura TSX runs on premium unleaded (required).
The 2011 Acura TSX runs on premium unleaded (recommended).
The 2010 Acura TSX runs on premium unleaded (required).