Where is the Bank 1 Sensor 2 (O2 sensor) on a 2008 Saturn Astra

Question

I keep getting the P0141 error on my 2008 Saturn Astra.  The code says that the O2 level is reading too lean in bank one.  I looked up the code and it said that the downflow O2 sensor was likely bad.  I bought a downflow O2 sensor, but the light came back on.  My brother replaced the only O2 sensor he saw at the front of the engine.  Is there another O2 sensor that's the downflow?  And where is it?

Answer 1

Hi there

The downstream sensor is AFTER the catalytic converter and normally under the car. The front O2 sensor or upstream sensor is the one before the converter that you can see from under the hood.