ABNORMALITY DIAGNOSTIC DEVICE FOR CAMSHAFT ROTATING PHASE

摘要

PROBLEM TO BE SOLVED: To diagnose an abnormality in initial set of camshaft rotating phase. SOLUTION: In an engine in which a cylinder discrimination and the detection of operating angle of a camshaft to a crankshaft in a valve timing control device are performed on the basis of the signal from a first crank angle sensor synchronized to the rotation of the crankshaft and the cylinder judgment signal from a second crank angle sensor synchronized to the rotating of the camshaft, the cylinder discrimination is performed during cranking on the basis of these signals. When a normal discrimination cannot be performed (S1-S7 and YES in S7), the abnormality of initial set of the camshaft rotating phase is diagnosed when the frequency of non-establishments of cylinder discrimination exceeds a prescribed number after removing an abnormality by disconnection or noise (S8-S12).