P0133

Schematic:

After achieving closed loop fuel control when rpm is within a range the PCM will continuously monitor front oxygen sensor signal for 100 seconds. During this time the PCM counts the number of rich to lean and lean to rich switches. To be considered a switch voltage must go below 300 mv and above 600 mv. The PCM also keeps track of the time it takes to make the switch. The number of switches along with the time to achieve these switches are used to calculate the average response time to perform each switch. Also this information is used to calculate if the proper ratio of the switches is correct.

DTC PARAMETERS
DTC P0133 will set when the average O2S1 response times are greater than 1199 mS for rich to lean sweeps or lean to rich sweeps are greater than 600 mS.

- or -

Average rich-to-lean times + average lean-to-rich times are greater than 1200 mS and the following conditions are met for 30 seconds:
^ DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0171, P0201, P0202, P0203, P0204, P0300, P0301, P0302, P0303, P0304, P0336, P0440, P0442, P0446, P0506, P0507, P0601, P0602 or P1441 are not set.
^ Engine speed is between 1600 and 2400 rpm (manual) /1800 and 2300 rpm (automatic).
^ TP angle is between 8% and 15%.
^ Evaporative purge is commanded to 80% or greater.
^ Purge learned memory is greater than 220.
^ Engine coolant is greater than 75°C (167°F).
^ Engine has been running more than 200 seconds.
^ The system is in closed loop mode.

DIAGNOSTIC AIDS
Repair Procedure
1. The oxygen sensor wiring and connections should be checked for corrosion or loose connections.
2. The most likely cause of setting this DTC is contamination. This contamination could be caused by fuel, improper use of RTV sealant, engine oil, or coolant contamination.
3. The source of contamination should be identified and corrected before replacing the sensor.