Patent ID: 6213068
Filing Date: 2001-04-10
Classification: F01L,F02D,Y02T

Abstract:
A method for checking the operability of a variable valve control in an internal combustion engine having an intake manifold and wherein the state of the variable valve control contributes to determining the combustion chamber charge, the method comprising the steps of:providing a first signal indicative of the air mass actually drawn in by said engine via said intake manifold;forming a primary signal (HLS) for the combustion chamber charge from said first signal;providing a second signal formed from a desired value for the state of said variable valve control and at least one of the following: the position of a throttle flap, the pressure in said intake manifold and the rpm of said engine;forming an ancillary signal (NLS) for the combustion chamber charge from said second signal;comparing said primary and ancillary signals (HLS, NLS) and forming an index for the deviation of said primary and ancillary signals (HLS, NLS) from each other; and,outputting and/or storing a fault signal when said index exceeds a predetermined value.