ok i just found out that it is a oxygen sensor or something what is this and is it expensive to replace where should my girlfriend take her car

 

O2 sensor should be fairly easy depending on your level of mechanical ability and your girlfriends trust in you with her car. Basically it's a sensor in the exhaust system to tell the ECU how much oxygen is in the exhaust so it knows how much gas to be adding or subtracting for optimal performance and economy. I can't remember if the new bugs have 1 or 2 though. I believe they only have 1. It will require a special socket due to the wire that sticks out of it but it's basically like a bolt. You disconnect the wire from it's harness, unscrew it, screw the new one in, reconnect the wire. Job done. You may have to cut the connector off the harness side if you get a universal O2 sensor as they only give you a crimp fitting to attach to the wire. Also don't forget to put the heat shrink on if you go the univesal route.

Hope this helps.