First off, try giving these guys a call [FONT="]Caspers Electronics (847-247-0484)
Then try ebay. I'll ask a guy at work where he got his.
If in doubt you could get a tune from PCMforless.com and they can just shut off your rear o2 sensors permanently. The PCM wouldn't even know what one is.
To clear up any other questions on 02 Sensors, the front 02 are the important ones, they tell the PCM if the exhuast is rich or lean, and directly influence the A/F ratio commanded by the PCM in closed loop.
The ONLY purpose of the rear 02 sensors is to tell the PCM, if the catalytic converters are going there job or not. NOTHING ELSE. On OBDII cars 96 and up, the PCM at certain times runs a test on the cats and monitors the rear o2 sensors to see if the cats can respond according to the written in parimeters on the PCM.
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