I have a 94 celica with 108,000 miles on the main oxygen sensor that i had welded. My bro not knowing **** about cars snapped it off the bolt from the new headers when he was trying to screw it on. He was stupid in welding the old one he should of told me first so that i could buy a new one. I have a new ntk sensor on the 2nd oxygen sensor that goes in the front exhaust pipe. Any ideas of how the Oem denso o2 sensor will last?