exhaust sensors on the -E-TECH 16V

[BASHO]

What exactly do the 2 exhaust sensors on the -E-TECH 16V actualy control ?
I'm for cold start and idle on the upstream in the cast manifold and fuel on the downstream in the exhaust pipe just after the cat.
But---
---I realy am guessing as I know SFA about iether as fact.
Can anybody help me out on this ?

[07_aveo]

The upstream sensor measures oxygen content of the exhaust gas and tells the PCM whether it's running rich or lean and the downstream one monitors the efficiency of the cat to convert the exhaust gas into cleaner emissions.

[xiaogary]

The downstream sensor determine whether the cat is functioning. If not functioning, it will light up a check engine light.

[BASHO]

The downstream sensor determine whether the cat is functioning. If not functioning, it will light up a check engine light.

How do you dummy the ECU it into thinking the cats there --when it's not--and niether is the sensor ?

[mikedudley17]

the anti fouler mod. search for it on here in the how tos.