Replacement O2's
 

I went to the dealer today intending on buying replacement front O2's. They told me the Bank 2 sensors were both the same (F&R), and the Bank 1 sensors were the same (F&R), but that the part numbers for each side were different.

I thought we used the same part number for the front O2's, and a different part number for the rears? The rear's are disabled, and I'm just looking for the appropriate O2's for the pre-cat locations.

I had read some other threads indicating that with a higher duration ( I have a 228/228) cam it may help to use a rear O2 sensor in the front - but that seems to contradict the info given by the dealer.. :confused:

Below are the GM and AC Delco part numbers, and the locations of each of the stock replacement oxygen sensors. Basically, left side of car = GM part number 25312197 and the right side of car = 25312196.

AC DELCO Part #AFS98
Sensor, HTD OXY (Posn 1) OEM Sensor; Left Hand (driver side); In Exhaust Manifold (GM #25312197)

AC DELCO Part #AFS97
Sensor, HTD OXY (Posn 2) Right Hand (Passenger Side); Front of Converter (GM #25312196)

AC DELCO Part #AFS98
Sensor, HTD OXY (Posn 3) OEM Sensor; Left Hand (driver side); Post Converter (GM #25312197)

AC DELCO Part #AFS97
Sensor, HTD OXY (Posn 3) Right Hand (Passenger Side); Post Converter (GM #25312196)