Irregularity-detecting method for variable valve-timing type engine.

摘要

An irregularity-detecting method for a variable valve-timing type engine in which valve timing for at least each one of intake valves or exhaust valves in the engine is changed over by a hydraulically operated changeover mechanism, said method comprising steps of: detecting by a hydraulic pressure detecting (20) means an oil pressure in an oil supplying passage for supplying oil to the changeover mechanism; and determining by detection signals from said hydraulic pressure detecting means whether or not the oil pressure in the oil supplying passage has changed in compliance with an open/close instruction given to a valve means that controls supplying oil to the oil supplying passage so as to determine any irregularity in the valve timing changeover.