I live in southern California and over a month ago had the car battery replaced. I did some normal driving (275 miles) before the smog check. The smog check report states that the O2S and the CAT monitors were not ready. Then we tried to follow the drive cycles (found on several websites, some even claim to be Toyota drive cycles) for O2S and CAT over several hundred more miles at various speeds for various time periods and some with idle times. The car does not have any DTCs or MIL on at all. The car has been running very smoothly with good fuel efficiency. The car does not show any symptoms of a bad catalytic converter or a bad oxygen sensor. We also replaced the air filter, the engine oil, and the spark plugs last week. But the CAT and the O2S monitors are still not ready. Does any one have any suggestions on making these monitors ready? Thank you.


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