sounds similar to the code i just got today for a evaporative emissions (small leak) and i got no clue how to go about fixing it good luck fixing it though.
I do believe this would be the problem. Change these and you should be set.
1)Part# E6ZZ-9C915-A :It's the small plastic valve on a vacuum hose directly behind the TB against the firewall
2)Part# F57Z-14A606-BA: This is a metalic cylinder with a connector on one end and a T on the other. Make sure you put the vacuum line on the right side as flow direction does matter. This one is located under the AC Canister on the same line as the first valve.
look in the motot compartment and see if the are connected. mine for some reason wasn't connected. i cleaned them and put them back together and it was fixed.