The OBD11 scan of the O2 sensors looks good. The #1 sensor is operating in a saw tooth pattern and the #2 is nearly flat.
The #2 O2 sensor reads in mA and I cannot find the mA range that makes the ECM happy. Is there a preferred test example and the desired results parameter for the test?
With an expensive cat converter on the horizon, I would like to be sure.
Thank You
P0420 Catalyst effiency below thresold (Bank 1)
Operating in a saw tooth pattern that represent a failing 02 sensor or a degraded 02 sensor. If the front 02 sensor cannot work properly the catalytic convertor can not work properly Here is a 02 sensor from a Honda poorly operating.
Here is the same 02 sensor replaced (even though the low shows a miss) which now switches properly. The rear 02 sensor should not go below 0.450 volts too long. Honda has a TSB about the software misinterpeting the rear 02 sensor input as deteriating sensor. Where the ECM has to be updated. TSB # 12-052
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