obd code diagnosis

[redbaron]

My 98 Ti check engine light came on for the first time in 170K miles. I had the engine scanned (thanks to advanced auto parts) and received the following PO codes: 455, 300, and 302. I have checked the fuel cap gasket (and flipped), checked the air filter (clean), and checked spark plug 2 (clean inside, a small amount of oil in the sleeve), and cracked the oil fill cap with the engine running and found lots of suction. I would appreciate any thoughts, comments or recommendations.
Thank you,
Shawn

[familytruckster]

CCV.

[redbaron]

Thank you, "familytruckster." I'll give it a shot.
Shawn