2009 Mini Cooper Base 4 Cyl 1.6L
what is oxygen sensor bank 1 sensor 2
On a four cylinder engine there is only one bank - the O2 sensor 1 is upstream of the ctalytic converter (nearest the exhaust manifold) and the sensor 2 is downstream of the catalytic converter. The O2 sensors are not difficult to replace - be sure to spray (soak) the old O2 sensor threads liberally with thread lubricant beforehand. Try the 'How-To-Guides' feature on the AutoMD website for the specific steps to replace the O2 sensor.