Toyota Repair: Code 55 Check engine light, haynes manual, toyota camry

Question
I ran a diagnostic on my 92 Toyota Camry and got code 27 (sub o2) and code 55 in the Haynes manual it says knock control signal (v6 engine RH bank), problem with knock control system in ECM, trouble area ECM.  I would like to know how to fix this problem as it doesn't seem as if the knock control sensor need to be replace.  thanks for any help in advance.

Answer
Try replacing the sub O2 sensor and see if it fixes the problem, ignore the knock sensor code at this time, if replacing the sub O2 sensor doesn't fix the problem there is a more serious problem which may be a mechanical problem with the engine that is causing these codes.