Ford Repair Questions? Ask a Mechanic for Answers ASAP
Thank you for your question, my name is Steve and I am a fully qualified technician with over thirty years in the trade.
Bank one is the exhaust bank nearest number 1 cylinder, as your C-Max only has one exhaust manifold this is not relevant. Sensor 2 is the down stream sensor, that is the sensor after the catalytic convertor.
The mechanic should really know this.
Depending on what the code is, it may not necessarily be the sensor at fault, codes can be triggered up due to wiring problems or air leaks in the exhaust.
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