Hi, I have an Audi A3 1.6 8V (Engine code BSE) which failed the emissions today. After a throttle body clean, it managed to pass but right on the 0.20% CO limit. The lambda and ppm are good. The front O2 sensor is reading 2V and pretty steady, seems rather high. The rear sensor is at a steady 0.7V. Is it likely that the front O2 sensor is faulty or perhaps the cat? Any help much appreciated

Might be worth doing a diagnostic check to see if the car flags up any fault codes. Would be cheaper to change the o2 sensor first in my opinion. 

There's no fault code in any system on the car. I'm now wondering if it's a wideband sensor and that 2V is normal?

Could well be. I wonder if you're a3 ever had the emissions recall from Audi which might be playing up. 

I checked on the gov website and there are no outstanding recalls, and I believe the emission recall was for diesel only, although I could be wrong

42 minutes ago, Ryan12345 said:

I checked on the gov website and there are no outstanding recalls, and I believe the emission recall was for diesel only, although I could be wrong

Correct it was only for diesel. Sorry I naturally assumed you had the 1.6tdi