Any smog experts out there?

Maybe you can check to see if it is running in closed loop, or open loop when it is up to temperature.

Oxygen sensor related, regulating fuel air mixture.

Believe the Closed Loop is when it is running in pre set parameters.

Open Loop is when the oxygen sensor is up to temp reading the exhaust gases telling the computer the needed fuel air mixture.

Most oxygen sensors are 3 wire. One of the wires is for the built in heater to keep it up to operating temp so it will read correctly. That heat circuit could have failed, hence replace O2 sensor.

Evap system sealed proper? Can try new gas cap as they fail to seal after a while. ??? Usually get a check engine light with this one.

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