If anyone saw my other thread (http://www.g8board.com/forums/showthread.php?t=77105) they would know the issues that I have had with my G8. I just got word from the dealership that all of my issues were caused by a bad fuel pump. They told me that it would randomly lose pressure to about 20 psi. They are replacing it as we speak (under warranty) but part of me does not think that this was the issue. When I brought it to them, it was misfiring and backfiring into the intake. Symptoms that I've never seen with a bad fuel pump. I also was running lean in both banks. In the thread linked, you will find all the codes and issues that I have had in the past 2 months.