May not be obvious. And what could be off may be emissions. You can google for more ideas but I tend to fix this to avoid problems down the road. Your choice of course but I defer more to Dr. Google.
2004 Toyota Avalon oxygen sensor
CEL has P0136 oxygen sensor code for a while now. Car runs wonderfully. No odors. Gas, mileage or handling issues and light has been on for a while. It sometimes will go off for a while but then comes back. Going to get it looked at. What should I expect they could tell me is wrong as the car has not experienced any problem because of this situation. Thank you.
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