I recently had the check engine light come on in my 03 jetta gli 2.8l 6spd. I had the car read at an autozone, they read that it was an upstream O2 sensor. I have read some articles online, but was wondering if there was anything that would really need to be watched for, because I recently wrapped some money in cracking my oil filter housing cap... duh i know, something so simple. So i want to be sure to get this right and not be a complete idiot again.
Any response is appreciated.

Thank you.