I would find that hard to believe as well.

Did you investigate the evap purge and the fuel pressure regulator to make sure they are not letting vapors/ fuel into the intake stream. I think it would be pretty easy to temporarily check by pulling the hoses off them and plugging it capping them off so you don't have a vacuum leak and see if it improves.

 

I replaced the purge valve but haven't checked the regulator yet. I will try that one. Thanks.

 

I said regulator, but what I meant was the rail pressure sensor. I believe it has a vacuum hose that goes to it and if the internal diaphragm fails it can leak fuel into the vacuum hose?

 

Okay thanks, way easier than tearing into the tank.

 

Sorry it took so long to get back to this post but finally got it figured out. I ended up bringing it in to a shop. They told me that the MAF sensor was bad, which I had already replaced. Apparently I should have looked at the new sensor better because the new sensor I got had 6 prongs and the original sensor only had 4 prongs. So I guess I learned that I need to be more careful when replacing parts, but at least it's running good again. Thanks again for everyone's help.