Hi,
Recently, my car's CEL is up.(1998 Lexus ES300) Went to a shop, tested out it was the P1135 and P1155 code. B1S1 and B2S1
The dealer told me it is the upstream oxygen sensor. However, the price is expensive for me. So I decided to buy one for local auto parts store or online.
Then I find out someone said B1S1 and B2S1 suppose to be Air Fuel Ratio Sensor instead of oxygen Sensor.
My questions are:
1. Is Air Fuel Ratio sensor the same as Upstream oxygen sensor?
2. Which One should I buy to repair my car?
