$17,500 for a car that you don't know is tuned properly or tuned for that BOV or the headers, will need a $300 timing belt kit soon, a $100 axle, $400-$600 for new tires. You don't know why its throwing a CEL. Just because it throws one for an o2 sensor doesn't mean it went bad. Something done wrong could've caused it to go bad. Not a car I'd wan a put money into. Take drews advice. Buy yourself a reliable car until you're out of college. And a year and a half of driving is not that much experience. I myself have been driving for 6 years and by know means call myself an expert and I've never had a wreck or a ticket either.