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I don't know if things have changed since I lived in Cali, but I think that you might want to stay away from that one. It isn't easy to get a newer out of state vehicle registered there and it sounds like you will be having to dump money into this one to meet the high standards. Unless you are 100% sure that it is only an o2 sensor, it could be costly. It may need a new cat or it could be any number of things relating to the exhaust system.