95 firebird check engine light

got a code <p0300b missfire> and a <p0441b evap control bad purge flow> any ideas on where to start checking for the problem??

did you ran a diagnostic as soon as the Check eng light came on? or you drove it like that for a while?....... Im asking this because at the dealer thats what they said, if you run a diagnostic as soon as the light comes on it easier to pin point the code( before the computer adjusts to what ever problem it encountered).