As mentioned to you on the day of service, the codes that you brought to us did not tell us what was wrong. They only showed a symptom. We had to take the codes and decipher what the possible cause of the codes were. As it was in this case, it could have been 1 of multiple issues, as explained to you.
Example: P0133 - HO2S Sensor Circuit Slow Response (HO2S-11) The HEGO Monitor checks the HO2S Sensor frequency and amplitude. If during testing the frequency and amplitude were to fall below a calibrated limit, the test will fail.
Contaminated HO2S sensor.
Shorted /open wiring.
As it was, we spent the hour of diagnosing, trying to figure out why the codes were being generating.
It is too bad that a code doesn't mean one bad component.