16804 code

[Mr Roboto]

Hi

I'm getting this fault code appearing every day now.

Is it the lambda sensor playing up?

I got rough idle, Hesitation on acceleration and increased fuel consumption.

16804 P0420 Catalyst System,Bank1 Efficiency Below Threshold

 

[James_R]

could either be the probe or the cat.

 

[Mr Roboto]

I think there is 2 sensors one in the down pipe and one in the CAT

Does blank1 mean the sensor in the cat?