Failed emmission test
PO327 knock sensor 1 circuit low(bank 1 or single sensor)
PO420 Catalyst system Efficiency below threshold(bank 1)

replaced cat for the pipe coming out of 1,3,5,7

ready to replace the knock sensor, however only see the one from the bottom on bank 2 side. Where or does it have one for the bank 1 side?

other info: replaced oxygen sensors
dist. assembly
wires,plugs
Spider is pretty new, changed it about 15,000 miles ago with new rebuilt.

any help on the bank 1 knock sensor location?