I have a '91 318is and was wonderiing if I have an O2 sensor on the cat itself or would removing the cat cause sensor malfuntion? and poor driveability. I've heard some guys smash out their ceramic insides and some will cut open the cat , remove the ceramic and then weld it shut . Whats the best thing in your guys opinion? has anyone messed with their cat? Is it hard to pound out the stuffing ? Can I remount the sensor somewhere else if I have to?
thanks in advance.
thanks in advance.