A method, system, and engine are configured to determine a parameter based on rotational speeds of a crankshaft, over at least three cylinder combustion cycles. The method, system, and engine determine two or more estimated crankshaft rotational speeds at two or more positions in a leading cylinder combustion cycle, two or more estimated crankshaft rotational speeds at two or more positions in a middle cylinder combustion cycle, and two or more estimated crankshaft rotational speeds at two or more positions in a following cylinder combustion cycle. The method, system, and engine are configured to determine a calculated metric based on each of the determined leading estimated crankshaft rotational speeds, the determined middle estimated crankshaft rotational speeds, and the determined following estimated crankshaft rotational speeds. An engine parameter, such as misfire, is then determined based on the calculated metric.
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