Contour Enthusiasts Group Archives Forums General Troubleshooting Chronic intermitten Engine light on and off

If you are getting an intermittent CEL, then there is probably something that is starting to go bad. It's best to take care of it from the start. If you don't, then other stuff can go bad as well (sort of like a domino effect).

Even though the CEL goes off, it is still stored in the car's computer for a while.

P0133 and P0153 can be caused by various problems. Most people throw a new O2 sensor at the code and hope for the best. But there are other reasons that the code can be thrown.

The following is from the Ford TSP (Technical Service Publication) on P0133 and P0153:

Diagnostic Trouble Codes (DTCs) P0133 and P0153 indicate the response rate of the HO2S is below some calibrated window.

DTC/HO2S Reference List:
DTC P0133 = HO2S-11
DTC P0153 = HO2S-21

Possible causes:
-- Contaminated HO2S.
-- Exhaust leaks.
-- Shorted/open wires.
-- Excessive fueling.
-- MAF meter.
-- Air leaks.


FYI: In the future, if you have an Autozone in your area, they will read the CEL code for free.