[Sensor 1] Oxygen Sensor Diagnosis, Replacement, and Maintenance

Has anyone replaced this sensor? I'm have a P0420 DTC that comes and goes and about due to replace the O2 sensors. Sensor one in front of cat converter switches between 250 mv and 700 mv about 40 tines a second as each cylinder fires at 600 RPM idle. Sensor 1 would be the upper sensor BEFORE the catalytic converter. You will find the upper's right under the hood in the exhaust manifolds, very ... Sad to say Bank 1 Sensor 1 is the upper one near the firewall.. But I recently did this on my 2G MDX and I can assure you its easier to replace ... Nifeida 13474 Oxygen Sensor OE Fitment O2 Sensor 1 Sensor 2 Upstream Downstream Auto Parts Fit 234-4018 AFS106 Replacement For Buick, Cadillac, Ponti. GM Genuine Parts Heated Oxygen Sensor Post-Catalyst Bank 1 Sensor 1. GM Part # 12705534. ACDelco Part # 12705534. Quantity Starting at $66.68. Bank 1 is the exhaust manifold for the first three cylinders of your in-line six, counting from the cylinder closest to the front of the car. BOSCH 17321 Premium Original Equipment Oxygen Sensor - Compatible with Select Ford Expedition, Explorer, E-Series, Flex, Focus, F-Series, Mustang, Taurus, ... OXYGEN SENSOR BANK 1 SENSOR 1 LOCATION, O2 SENSOR LAMBDA If you have engine light and code that relates to oxygen sensor bank 1 sensor 1 and ... Did you replace B1,S1 and B2,S1, if so that's both the Air/Fuel Ratio Sensors and not the actual O2 sensors? From the part number it looks like ...