)EIB(

CEL comes and goes from time to time. Scanned it and found 1 stored code showing P0150 which is the O2 Sensor Cicuit Bank 2 Sensor 1. So I'm planning to replace the sensor and hopefully that fixes it. I just wanted to check and see if I should replace all 4 sensors at once. And where is the best place to buy the sensors?

Thanks.

MarcusF

When I thought they were due, I replaced all 4. The primary (front) sensors are the only ones that impact drivability. The rear two are only used to check the condition of the catalytic converter. If I were you, I’d replace the front two. "IF" you get the right Bosch direct fit sensors, they should be fine. If you buy the universal sensors, I hope they work better than mine did. RockAuto has them, and they have a very good return policy.

)EIB(

Thanks for the quick reply.

So Bank 1 & 2 are the left and right, and Sensor 1 & 2 are front (upstream of cat, pre-cat) and rear (downstream of cat, post-cat), correct? The Bosch description refers to upstream left/right and downstream left/right. But is left being the driver side and right being the passenger side, or vice-versa?

On the Bosch direct fit ones, are the connector different for each? So, one cant really mess up, right?

nd4spd13

Bank 1 refers to the side of the car that Cylinder 1 of the engine is on. Usually it's bank1 = driver, 2 pass, but it could be different