O2 Sensors

[demus82]

Hi fellas, quick question on 2 02 sensors. I got the codes of the odb and want to replace them. However, I did not know which sensor to buy based on upstream or downstream.

P0141(Bank 1, Sensor 2)- upstream or downstream?
P0155(Bank 2, Sensor 1)- upstream or downstream?

[vr4gto]

Downstream is heated
http://www.evoscan.com/technical-vehicle-manuals/63-obdii-diagnostic-trouble-codes

[demus82]

Cool, so from that list, both say (heater). This means downstream right?

[vr4gto]

Yes, the heated O2 is downstream

[Gotti]

4cly b1s2 is the p/s downstream. B2s1 is driver side upstream
V6 b1s2 is the rear exhaust manifold down stream. B2s1 is the front exhaust manifold upstream

[huskerinaz]

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