02 sensor identification??

[bigbrdf250]

How do I know what a upstream or downstream 02 sensor is. I know up is first from the mani but cannot tell on my set up. I have a aftermarket housing and its got 2 o2 bungs. One is the wide band and the other a factory sensor. Looks like they all scavenge in the same way after the turbo. Is this right??

I need a factory plug and play to make it easier for me. Thanks.

 

[snowborder714]

Well, a downstream sensor is typically downstream aha from the turbo. In the case of factory sensors, only 2g's have a downstream sensor which checks for a functioning cat only. Both 1g and 2g have upstream o2 sensors (which sit in the o2 housing) and send the ECU a signal which it uses for fuel trims.

 

[bigbrdf250]

Ok, thanks for ## help.