So I bought a 2009 Cobalt with 109k and have had issues since buying it a month ago. From what I can see, it is bone stock with a what is more than likely a Stage 1 tune (it has the 3-bar sensors). CEL came on after about a week, and I have replaced the plugs, coils, purge solenoid, oil, and run a boost leak test to find and fix any leaks. The code is P2096, which is a post catalyst fuel trim system too lean on bank 1. It has now been 2 weeks, and the CEL came back on and the car will start sputtering and losing all power, eventually stalling out, with an occasional small backfire.
So now my question is, is my intercooler cracked? Or is it an issue with my fuel pump? After fixing everything else I can find, that is the only thing I can think of that may be causing this. Suggestions would be helpful!