Outline Of Diagnosis: Notes

To detect malfunctions, the diagnostic uses a predictive model, individual cylinder fuel control, and the primary oxygen sensor measurement. The diagnostic does not directly attempt to separate the primary oxygen sensor measurement into individual cylinder contributions, but uses a predictive model to do so. Individual cylinders STFT are independently adjusted to obtain the moving 720 degree average lambda of all four cylinders using feedback from primary oxygen sensor. If any individual cylinder's STFT is different than the average of the other cylinder's STFT by a calibrate-able amount, that cylinder will be identified as failing.