Misfire judgement
Misfire judgements are delayed by one firing cycle. This is to allow comparison of the signal with the cylinders that fire before and after it, eliminating 'noisy' signals. Should the monitor repeatedly eliminate the signal over 5 consecutive firings on the same cylinder the monitor will assume that two adjacent cylinders are misfiring, ignore the signal check and allocate the 5 eliminated misfire judgements to the appropriate cylinder.
Adapted and un-adapted signals are compared to their respective thresholds in series. The diagram below illustrates the behavior of the 'adaptive' misfire signal with 1.0% intermittent misfire applied (data taken from a typical 8 cylinder application) and its judgement threshold.
Should one signal cross the threshold, indicating a misfire, the other methods will be skipped in order to prevent multiple counting of the same misfire event.