First off I would like to say hello to everyone as this is my first post. I will try to keep this short but hope to give enough information to get the answers I need. 2006 model CTS 3.6L 159000 miles. This car is fairly new to me. I have DTC codes P2187 P2189 PO 300 301 and 303. In pending codes I have all the previous code as well as PO 304 and 306. I know what the definition of all these codes are but am really unsure where to start. I'm leaning toward fuel filter or fuel pump problems but I don't just want to throw parts at it. Symptoms start with a miss as you started up a hill or under a load but now have gotten to where it happens while driving at a normal pace. Any help would be greatly appreciated. Like I said I'm new here so I hope I'm in the correct place. Thanks