1. A misfire detection apparatus for detecting misfire of an engine, said engine having an engine speed and a manifold absolute pressure, comprising: an engine signal preprocessing system for determining a fluctuation associated with the engine speed and an average associated with the engine speed and an average associated with the manifold absolute pressure; an input to a neural network for providing as an input to the neural network the determined engine speed fluctuation, said neural network determining a firing event signal based upon said determined engine speed fluctuation and upon said determined engine speed average and upon said determined manifold absolute pressure average; and a misfire decision determinator for detecting a misfire of the engine based upon said determined firing event signal.