CONTROL DEVICE OF INTERNAL COMBUSTION ENGINE

PROBLEM TO BE SOLVED: To provide a control device of an internal combustion engine, which can accurately perform failure determination of a device relating to the internal combustion engine by using a detection result of an oxygen concentration sensor for detecting oxygen concentration in exhaust gas.SOLUTION: A control device 1 of an internal combustion engine executes failure determination of a device relating to the internal combustion engine 3 by using a detection result of a LAF sensor 32 for detection oxygen concentration in exhaust gas discharged to an exhaust pipe 30 of the internal combustion engine 3, and has a variable valve timing mechanism 8 capable of changing valve close timing of an intake valve 4. The control device comprises control means 2 which controls the valve close timing of the intake valve 4 to a more delay side than the bottom dead center of a piston during normal operation of the internal combustion engine 3 and controls the valve close timing of the intake valve 4 to a more advance side than that of the normal operation when executing the failure determination. 【課題】排ガス中の酸素濃度を検出する酸素濃度センサの検出結果を用いて、内燃機関に関連するデバイスの故障判定を精度良く行うことができる内燃機関の制御装置を提供する。【解決手段】内燃機関３の排気管３０に排出された排ガス中の酸素濃度を検出するＬＡＦセンサ３２の検出結果を用いて、内燃機関３に関連するデバイスの故障判定を実行するとともに、吸気バルブ４の閉弁タイミングが変更可能な可変バルブタイミング機構８を有する内燃機関の制御装置１であって、内燃機関３の通常運転時に、吸気バルブ４の閉弁タイミングをピストンの下死点よりも遅角側に制御するとともに、故障判定の実行時に、吸気バルブ４の閉弁タイミングを通常運転時よりも進角側に制御する制御手段２を備えている。【選択図】図２