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O2 Sensor/ Check Engine Light On then Off

My 2014 Chevy Malibu has its check engine light come on and when I plugged a code reader in it it said bad O2 sensor but the next day the check engine light was off and when I plugged the code reader in it it said nothing… any help?

The OBDII system turns the Check Engine light on when there’s an issue with the emission control system.

If the problem no longer exists, the OBDII system turns the Check Engine light off.

More than likely the problem is with a lazy O2 sensor.

Tester

Suggest to post the actual diagnostic code number. There’s no diagnostic code for a bad O2 sensor. The codes are for O2 sensors that produce unusual readings, or open circuits in the case of heated sensors, either of which may or may not be caused by the O2 sensor ass’y itself. If you’ve got an O2 sensor problem remaining, the check engine light will come back on again.

https://www.obd-codes.com/p0133

Tester

Generally that means it’s on its way “out”.

Aren’t oxygen sensors covered under 7/70 or 8/80 in some states . . . ?

Not that I’m aware of.

Since 1996 (OBDII), the emission components covered under the mandated EPA warranty regulations for 8 years/80,000 miles are the catalytic converter(s)/emission control computers.

All other emission control components are warranted for 2 years/24,000 miles.

But any mechanic should know this.

Tester

There is a long list of emissions covered components covered for 7 years/70,000 miles in the state of California but oxygen sensors are not on the list.

PZEV vehicles have a complicated emissions warranty that differs by state. Light trucks over 8500# are covered for 5 years/50,000 miles. Warranty requirements have changed so much since 1996 it is best to check warranty coverage for each case.

Thank you for the answer

That was helpful, and respectfully worded

Thank you

:smiley: