Depends on year to 93 there are 2. 94 and later there are 3 (one post cat)
in the car
It is caused by Bank 2 Sensor 2 oxygen sensor failing.
inside the exhaust and by dissasembling and swapping it out
18 Millimeter, 1.5 Pitch
Let me know if you find out. i am having trouble locting which one is 1 and which is 2... I was told i needed to replace the #1 oxygen sensor
On a Lexus RX 300, the oxygen sensor is typically located in the exhaust system. There are usually two sensors: one before the catalytic converter (upstream) and one after it (downstream). The upstream sensor is generally found on the exhaust manifold or in the exhaust pipe close to the engine, while the downstream sensor is located after the catalytic converter. Always consult the vehicle's service manual for precise locations and specifications.
The sensor runs under the seat and out to the exhaust pipe under the back of the car. You will have to remove the two bolts holding the seat to replace it.
Cylinders 1,3, and 5, the sensor after the catalytic converter. Find the exhaust pipe coming from the front of the vehicle and follow it until you see the O2 sensor after the catalytic converter.
To replace the oxygen sensor (sensor 1, bank 1) on a Lexus SC 300, first, ensure the engine is cool and disconnect the negative battery terminal. Locate the sensor, typically found on the exhaust manifold or upstream of the catalytic converter, and unplug the electrical connector. Use an O2 sensor socket or wrench to carefully unscrew the old sensor, then install the new sensor by threading it in and tightening it securely. Finally, reconnect the electrical connector and the battery terminal before starting the vehicle to check for proper operation.
In a 2002 Lexus RX 300, Sensor 1 Bank 1 refers to the upstream oxygen sensor located on the driver's side of the vehicle, before the catalytic converter. To replace it, first, ensure the engine is cool and disconnect the negative battery terminal. Then, locate the sensor, unplug the electrical connector, and use an oxygen sensor socket or wrench to unscrew it from the exhaust pipe. Install the new sensor by reversing these steps, ensuring it's securely tightened and the connector is reattached.
It is under the intake manifold
The 2001 Lexus coolant temperature sensor can be found on the front of the engine. The coolant temperature sensor will be in the vicinity of the thermostat housing.