Hi. I own a 2004 pontiac gto with a m6. I was recently driving it and it started to bog down if i didnt give it gas. I made it home and got it into my driveway. It has sat there for 3 weeks now. When i go to start it, it will idle for a second then immediately bog down and die. If i give it gas constantly it will run, not smooth, but it runs. Any ideas?