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imakedrinks88 t1_j3ntxb7 wrote

After a quick look in your post history and seeing you rebuild a WRX and having evap and O2 monitors not set, I wonder if your ECU is tuned.

Some tunes will turn off your secondary O2 sensor in order to help maintain a certain A/F ratio.

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crankshaft123 t1_j3o0zzw wrote

Turning off the downstream 02s via tuning or coding usually makes the monitor show up as N/A or NOT SUPPORTED on an OBD I/M test. The state computer will typically allow that to pass.*

*I haven't done an emissions inspection in 3 years, but this info was correct as of 01/2020.

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belleayreski2 OP t1_j3schy6 wrote

I do have an OTS tune, but I still have all of the smog components like Cat, O2 sensors, etc. I have been able to set the monitors in the past.

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belleayreski2 OP t1_j3saog8 wrote

It's an OTS tune from Cobb that goes with the exhaust and intake, but it hasn't stopped the readiness monitors in the past.

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