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Old 02-03-2012, 08:30 AM   #10
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Well, its worth a shot before doing anything drastic, thanks for looking it over! The rear sensor had zero output before I started troubleshooting, that was replaced, the front is original with 95k miles on it. Hopefully the cat is happy. Oddly enough, after a drive to warm it all up, at idle, the rear sensor smooths out quite a bit but not while driving.

So O2S11 (sensor 1 front?) is just a tick higher in voltage from O2S12 (sensor 2 rear?) A newer front sensor would increase the voltage and put it closer to happyland? its an easy parts swap so I'll try to knock that off today. Today shows a P0420 in pending status
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