02 Sensors

[Maeda]

So I busted the one after the cat, and the one before the cat doesn't fit into my down pipe.... Since they're just for the ECU couldn't I just cap the holes and not use any o2 sensors in the exhaust system?

Ideas?

[TurboKA37]

i think u could do this but u will be running with a check engine light on. im not 100% sure but i dont think the ecu uses the O2 sensor measurements for anything but emission warnings

[4felix20]

damn, I need that same friggin o2 sensor. It's driving me nuts and the OE replacement is like 90$ at some places.

A universal won't fit...will it?

[jacob360]

When the (OBDII) system is in closed loop, it uses the first O2 sensor as an indication of air fuel ratio to keep it crosscounting rich lean around stoichiometric (14.7:1) to ensure proper operation of the catalytic converter. The second (post cat) O2S is used to monitor catalytic converter efficiency. When you're at WOT, the system switches to open loop, and uses the preprogrammed maps. If you unplug your O2 sensors, the PCM will set a code, turn on the check engine light, and run in open loop (rich).

[Maeda]

Ok I guess that means I need the first sensor at the very least....

Could I use the smaller sized back sensor as a replacement for the larger first sensor?

My downpipe's hole only fits the smaller of the two....

[jacob360]

The sensors themselves are most likely the same. As long as the threads and connectors match up, you should be able to.

[Maeda]

thanks! I'm gonna try it today ^_^although I won't know the results until im finally boosted...