960 - B230FT - Exhaust looks a bit dark

the sensors each do their own separate thing one for the gauge and the other the ecu.

Purely an assumption but if the knock sensor has failed it would probably run rich rather than lean as a fail safe.

doesnt seem too excesssive , your lambda sensor and AMM are more likely to be culprits in that scenario . ECU will now re learn , so do some service items /clean the breathers etc .