Vent valve
 

I had a diagnostic ran on my truck today about my check engine light. I thought it might just be I need a new gas cap. For the past four months I went to Advance Auto Part to clear the code and I was told to buy a new gas cap. After four months of the same thing I got fed up. So I went to the dealership to take another look. It threw a P0455. They told me it is a bad Evap vent valve. Does anyone know where it is and how to fix it? The dealer offer to install a new one for $317. I'm pretty handy with a wrench, if not too complicated I'm sure I could buy the kit and swap it out. Any help would be greatly appreciated. I had the P2771 and a C0327 fix today also it was a bad encoder motor on my 4wd.

Thanks,
Tom

This should be the same as yours I think it is #2 -

http://gsi.xw.gm.com/image_en_us/gif...06/1606458.gif