EJ8_Enthusiast

I am going to try to move my O2 sensor away from the cat - but if the o2 sensor is bad, there is no point.

I know I can check it with a multimeter, but how? none of the wires are exposed, just two black a white and a blue going up into the floorboard.

Where can I get a voltage reading without cutting into any wires?

car is up in the air so if you got any clues, please indulge me

xci_ed6

T-pins are your friend.

back probe the connector with a t-pin.

EJ8_Enthusiast

all too simple. thanks.

slowcivic2k

You will not get rid of that code without having a working catalyst. The upstream O2 sensor cycles from about .1V to .9V, and the downstream cycles much slower, at around .4V to .6V. That indicates the exhaust is being scrubbed by the cat, a bad cat, or no cat at all will cause that code.

If the O2 sensor was slow, reading high or low, the ECU would trigger the appropriate code. It doesn't matter where you put that O2 sensor, it will come back.