To accurately detect VVT malfunction of a vehicle such as economy running vehicle.
When an ECU (electronic control unit) judges whether engine speed is a threshold value or more, or not, the ECU detects times of VVT advancement angle calculation after engine restart and judges whether the times of VVT advancement angle calculation is a threshold or more, or not. The ECU detects VVT advancement angles and judges whether the VVT advancement angles is a threshold value or more, or not. When the ECU judges whether an engine is in an engine stop sequence or not, engine speed is the threshold value or more, the times of VVT advancement angles is the threshold or more and the engine is not in the engine stop sequence, the ECU executes a program setting a VVT malfunction judgment permission flag and detecting VVT displacement and determining VVT malfunction if the VVT displacement is less than a judgment threshold value.
Toshio Morita
Tadashi Muto
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