i have a decat centre pipe on my exhaust connected to standard downpipe with its cat, but my emissions are through the roof

could the fault code flashing 22 - knock sensor have anything to do with my high emissions ?

 

yeah, all linked to the timing. Change the water temp sensor too if you can, pig off a job though. Just had to change both knock sensors on my svx, timing was out and it was drinking petrol not that it doesnt anyway. Check the lambda sensor too, my old impreza failed the mot on that.

 

even before this code started flashing my emissions were high