C200K O2 Sensor
"P0134 O2 sensor heater Circuit bank 1 sensor"
I presume it is the sensor before the CAT. The questions are:
how easy is to change? and where the sensor is located? Would this be the right part?
http://cgi.ebay.co.uk/LAMBDA-SENSOR-...item518fbce305
Your help is greatly appreciated.
Regards,

That is the pre cat sensor on the M271 - You can see it from the engine compartment just below the manifold & above the Cat.
That looks like a generic sensor. Buy the Genuine Bosch part number for your car with the correct plug on it. Generics have a bad habit of giving trouble on these cars even if they are Bosch generics
With the correct crows foot 22mm tool it is not too difficult but the sensors can seize in the pipe requiring persuasion (FBH). Fit new sensor with anti seize compound on threads.





