My 99 wrangler has the cat cut off. I've been running it that way because that's the way it was when I bought it. I'm about to put one back on, and wonder.....will a "universal" one work? I'm having some sputtering/bucking issues, and my fuel mileage has gone to hell. Those are all symptoms of a faulty o2 sensor, according to google. I'd pull my hair out, if I had any..... Can someone please help? Foul language sure hasn't!