Patent ID: 6668547
Filing Date: 2003-12-30
Classification: F02D,F02P,Y02T

Abstract:
A method for protecting a catalytic converter in the exhaust system of an internal combustion engine from overheating during a retarded ignition angle, said method comprising the steps of:supplying a characteristic map having at least one of an engine-speed and a load-dependent specified ignition angle which is specified without time restrictions; comparing said specified ignition angle with an optimum ignition angle calculated in a perimeter-dependent manner; utilizing said optimum ignition angle for ignition of the internal combustion engine during specifiable time periods in alternation with the specified ignition angle when said optimum ignition angle is more retarded then the specified ignition angle wherein said specifiable timer periods are specified as a function of engine speed; utilizing only the optimum ignition angle for ignition of the internal combustion engine when said optimum ignition angle is more advanced then said specified ignition angle.