Need some advise on a P0445 code...

[bmx672]

Hey guys (and girls)
So the other day the Boxster threw this code (P0445)... I read it and it seems that it could be a pressure leak in the fuel system (Possibly). So I check the gas cap and it looks to be fine (Since thats an easy test)...
Soooo, today I start the car and it idles fine for about 15 seconds then dies... I tried later and the same thing... My question is this... could a dirty/bad MAF sensor cause this to happen (throwing a p0445 code)? Pulling the MAF and cleaning it is easy... But before I get too deep into this I'd like to see if anyone has ever thrown a 0445 code and what the remedy was.
Could bad gas make your car do this? This code came up about two mile after I put gas in the car. I'm not sure if that was just chance...
I appreciate any responses.

It figures the first nice weekend I have this problem! This is my 5th summer with my 2000 Box and this is the first time its ever thrown a code

[JFP in PA]

You have a large vacuum leak in the EVAP system (behind the passenger's side wheel well liner). If you are certain it is not the gas cap (check the o ring seal on the cap to be sure) as you said it happened just after refueling. System consists of a charcoal canister, several valves and vacuum lines, anyone of which can be the culprit. It is not a MAF related issue.

[bmx672]

Thanks for the reply! looks like I have my Sunday all planned out!
I'll let you guys know what happens!

Thanks again!

[bmx672]

Now that we're on the subject... I've had that problem the last few years where my gas tank will not fill up past half way. I've always figured it was the slipped tube problem in the tank... now I wonder if there's anything in the EVAP system up top that could also cause this problem? I've done the typical fuse check etc.
Any thoughts on that guys?

Thanks.