Rear oxygen sensor can cause emissions failure on Toyota Corolla

The rear Oxygen sensors are a critical element in fuel control (unlike other vehicles) and can cause an emissions test failure for high CO and HCs. The sensing element cracks and and reports an erroneous steady state lean condition which confuses the engine computer.
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Average mileage: 128,500 (25,000–275,000)
7 model years affected: 1993, 1996, 1997, 1999, more2005, 2007, 2010
10 people reported this problem
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problem details
2010 Toyota Corolla 100,000 mi,
lot of problem with the power, to take gaz
exhaust sensor failure - $300 repair bill