[JoeShmoe]

Originally Posted by george536

the correct way to test an o2 is to make your car rich with propane and make sure it goes to passed .9v and make it lean and see if it goes lower .175v if it doesnt go passed those it is considered biased. then the only real way to test if it is functioning correctly is to have a Oscilliscope and do a "snap test" and record it, which basically is when you make it rich with like propane and then remove it and wait for it to switch to lean then snap the throttle and record the switch from lean to rich and make sure its under 100ms switching time. well this is the procedure for the first o2. the rear is only used to make sure that the front and rear do not match up. if they do the efficiency of the cat is bad. the cat is there to reduce emissions and should put out a steaady oxygen reading thats why the rear and the front wont match up. since the front is constantly changing. so even if those o2 sensors are "lazy" on switching it wont matter since all it checks for is that it doesnt match up. so you can put it and it wouldnt make a difference if the o2 was dead. i hope that makes sense

O2 Sensors 101, LOL. UI thik I get it now, makes perfect sense. Don't know where to go with this though.