Can anybody tell me where the O2 Sensor in Bank 1 Sensor 1 is? I called Acura and twi different techs there DID NOT KNOW! Thanks in advance.

-Baum

 

There is no bank 1/bank 2 02 sensors, just pre and post cat (its actually in the cat)

 

The first o2 sensor, the primary o2 sensor, is at the end of the headers where they connect to the cat and the second is on the cat itself. Where did you get your terms from? diag tool?

 

I got it off the OBD2 code reader that said "O2 Heater Sensor Malfunction, Bank 1 Sensor 1". So if I go off of that from what you're telling me I'm looking for the sensor at the end of the headers where it connects to the cat? If it's there then why would the stealership charge $250-300? I know that's why it's called the Stealership. Thanks guys I ordered the part tonight should be here tuesday.

 

Yep your correct. Bank1/sensor 1 is the primary & bank 2/sensor 2 is the 2nd one. o2 sensors are $.

 

Wierd, I have been looking through my service manual since I posted and I cant find anything in it refering to the 02 sensors as bank1 and sensor1/2. Am I retarded or is it somewhere else in the book. I only have the codes and what they mean and they indicate primary and secondary only.

 

It's not CL specific. It's general automotive knowledge. All new cars have at least 2 o2 sensors for emissions.

There a primary & secondary the primary is always the 1st 02 sensor in the exhaust system. The secondary is always the next in line to that.

Todays cars ECU's must measure the emissions from the engine before it gets to the cat & after or during it's pass through the cat. The ECU will then determine the correct fuel mapping to ensure the car runs right & the way it's designed.

Older cars didn't need this to much. But I have had OBD1 cars that had 2 o2 sensors. Some 3 or 4.

They can be referred to as...

primary/secondary
bank1/bank2
heated/unheated
there are several ways to describe them.