Hi Scotty,
I have a 2007 Mazda3 with approx 183,000 kms/ 114,000 miles. It has P0138 O2 Sensor Circuit High Voltage (Bank 1, Sensor 2) code. It only seems to come on in the morning if either I leave the auxiliary port or if I leave the car idling to warm in the morning (it’s been at the freezing mark in the morning). By the commute home it goes away (or if I don’t idle it)
The rear heated 02 sensor heating element is probably burned out.
I like to use Bosch 02 sensors. After all, the Bosch company invented the 02 sensor.
Am I correct in assuming that you believe this should not be ignored and could result in further damage?
This sensor's only job is to monitor your catalytic converter's efficiency. (pollution control)
It is not required to make the engine properly, and cannot damage it, but it is Federal law to have functioning pollution equipment.
Thanks for the reply and the recommendation for the brand.
Am I correct in assuming that you believe this should not be ignored and could result in further damage?
Again it comes on if I warm up the car on idle but goes away later in the day, or doesn’t seem to come on if I don’t warm up the car and just drive
Thanks I appreciate it, thankfully there is no federal law in Canada, and in BC they ended emissions testing after 2014 as vehicle