O2 sensors pre- and post-cat

[Gary Derian]

The cat stores O2 so the voltage swings more slowly in the downstream
sensor.

Gary Derian <gderian at cybergate.net>

-----Original Message-----
Subject: O2 sensors pre- and post-cat


>If standard O2 sensors only work at a single O2 %, and the cat itself is
>changing the O2 concentration in the exhaust stream, and the ECU is cycling
>the pre-cat sonsor around its optimum ratio, then what does an ECU expect
>the post-cat sensor to be telling it?
>
>Just curious.
>
>Mike