Bank 2 is the drivers side of the engine sensor 1 is in the exhaust , close to the engine , before the exhaust passes through the catalytic converter
The oxygen sensor for bank 1 sensor 1 for a 2000 mercury mountaineer is on the cylinder #1 side.
On a 2000 Mercury Mountaineer ( 4.0 V6 and 5.0 V8 ) Bank 2 is the drivers side of the engine Sensor 1 is close to the engine BEFORE the exhaust enters the catalytic converter Sensor 2 is AFTER the exhaust has passed through the catalytic converter
Try replacing the upstream O2 sensor
For a 1997 Mercury Mountaineer ( 5.0 liter V8 ) ( there are a total of 4 oxygen sensors , 2 sensors that are used with the PCM to adjust the fuel ratio that are nearest the engine on both sides , and 2 sensors that are also called catalyst monitors because they are in the exhaust after the catalytic converters ( downstream sensors ) On the passenger side of the engine in a Mercury Mountaineer ( Bank 1 ) Sensor 1 ( upstream sensor ) and Sensor 2 ( downstream sensor ) On the drivers side ( Bank 2 ) Sensor 1 ( upstream sensor ) and Sensor 2 ( downstream sensor )
Trouble code P0153 means: HO2S-21 (Bank 2 Sensor 1) Circuit Slow Response Try replacing the upstream O2 sensor
P0133 - upstream heated O2 sensor circuit slow response ( Bank 1 ) Bank 1 is the passenger side of your engine Sensor 1 - is in your exhaust pipe before the exhaust enters the catalytic converter ( upstream )
P1131 = Insufficient switching O2 Bank 1 Sensor 1 Sensor/lean. Could be a B1 S1 O2 sensor going bad.
Bank 2 is the drivers side of the engine on your 1999 Mercury Marquis Sensor 1 is before the catalytic converter ( upstream ) Sensor 2 is after the catalytic converter ( downstream )
The bank 1, sensor 3, O2 sensor would be the O2 sensor post cat.
You did not specify which O2 sensor it is. Is it sensor 1 bank 1, sensor 2 bank 2, sensor 2 bank 1, or sensor 1 bank 2. There are four O2 sensors on a mazda 626
usually bank 1 is the bank with # 1 cylinder in it and sensor # 1 is the front o2 sensor(usually in the manifold). You will need a O2 sensor socket or a 22mm wrench or deep socket.
P0137 = O2 sensor circuit low volts (bank 1 sensor 2). Could be a faulty B1 S2 O2 sensor.