Bank 1, Sensor 1 Inactive - No CEL

[alanchau]

Hi,

I've been getting poor fuel economy recently and have trying to figure out why. recently noticed that Bank 1, Sensor 1 shows no activity in Torque. No CEL is thrown.

I previously had codes thrown that related to the O2 sensor but disappeared on its own. I don't remember the exact code.

Does Bank 1, Sensor 1 showing no activity indicate a problem with the O2 sensor? TIA!

[alanchau]

Forgot to mention that it's a 2008 Mazda 3 GS.

[Flagrum_3]

Hi,

I've been getting poor fuel economy recently and have trying to figure out why. recently noticed that Bank 1, Sensor 1 shows no activity in Torque. No CEL is thrown.

I previously had codes thrown that related to the O2 sensor but disappeared on its own. I don't remember the exact code.

Does Bank 1, Sensor 1 showing no activity indicate a problem with the O2 sensor? TIA!

Most likely! Would be my answer. But, also considering your poor mileage, I would suggest a new O2 sensor is in your near future.


_3