yes, it's threaded into the front of the front catalytic converter. that's bank 1 sensor 1. (bank 1 sensor 2 is threaded into the rear of the rear catalytic converter. in order for the car (more specifically the computer) to refine how well the engine will run, and also to keep the amount of pollutants headed out the tailpipe down as low as possible [especially carbon monoxide (CO), hydrocarbons (HC), and oxides of nitrogen (NOx)], the computer constantly compares the two (in this case) oxygen sensor readings (while the engine & computer are running "closed loop") and alters/tweaks/maintains fuel, ignition timing, spark, cooling fans, etc., in order to maximize efficiency. i just googled "oxygen sensor info," and this is the first website i saw http://mr2.com/TEXT/O2_Sensor.html ; it might give you a little more background theory about O2 sensors and how they work, in case you're interested. my idea is that if you understand how they work, why they work, and how to test them, you won't throw away money replacing parts that don't need replacing. good luck. The 2000 Subaru Outback has 2 oxygen sensors. One is located at the front of the catatlytic converter, and the second is at the rear of the catalytic converter. My best guess is #1 is at the front, but I'm not positive here. I'm replacing both anyway as I'm at 100K miles. David
On a 2005 Subaru Outback, Bank 2 Sensor 1 is located on the exhaust system, specifically on the passenger side of the engine. It is positioned upstream of the catalytic converter, before the exhaust gases enter the catalytic converter. This sensor measures the oxygen content in the exhaust gases to help optimize engine performance and emissions.
Right Hand Side (passenger side)...
The Bank 2 Sensor 1 Air/Fuel Ratio Sensor is on the left side of the Left Hand Front Exhaust Pipe, just below where it connects to the engine. Can't miss, it stands out like a sore thumb.....
In a 2002 Subaru Outback H6, bank 2 refers to the side of the engine that contains the rear cylinders. Since the H6 engine is a horizontally opposed six-cylinder engine, bank 2 is typically considered the passenger side of the vehicle. Conversely, bank 1 would be the driver's side.
The oxygen sensor for bank 1 sensor 1 for a 2000 mercury mountaineer is on the cylinder #1 side.
bank 1 sensor 2 is after the cat
Bank 1 sensor 2 would be the sensor after the behind the catalytic converter.
The 2000 Mazda Miata O2 sensor bank 1 is located on the firewall in the engine compartment. The sensor can be found on the passenger side of the firewall.
That should be the sensor after the catalytic converter.
bank 2 sensor 2 is the passenger side, rear sensor, it is located behide the catalytic converter.
Bank 1 is the driver side.
That should be the sensor located after the catalytic converter.