P0133

DESCRIPTION
Refer to DTC P0130 & P0136.

FAILURE CONDITIONS
The ECM will set P0133 and MIL will turn on if the ECM does not sense the following conditions during two driving cycles:

1. Over a period of 2 minutes, the ECM must sense a fuel compensation factor greater 85% or less than 95 %:
2. The ECM must make some correction in the air/fuel ratio when:
- Engine RPM is between 1600 and 3200 RPM.
- Engine load range is between 1.35 and 3.4 milliseconds.
- Catalyst temperature is above 372 °C (702 °F)
- System is in closed loop.

This code indicates the engine air fuel ratio is not being adjusted by the front oxygen sensor signal or the ECM as expected to do so, or not adjusted as often as expected to do so once the engine is warmed or under normal engine use.

Circuit Diagram:

Test Procedure Part 1:

Test Procedure Part 2:

Test Procedure Part 3: