cowfy

2006 chevy optra 1.6 made in korea.as is the aveo.was called to scan it and give opinion.idle jumps up to 3-4 k when starting.if we disconnect the map sensor she quites down but misfires slightly and once we reconnect and give a bit of throttle the revs jump up again.the the mechanic removed the codes before i got there and no codes at all show up with this crazy situation.he put in a new map sensor.and no difference.of course when i removed the connect to the map sensor a code showed up.are there any majic bullits here?