Patent ID: 6155043
Filing Date: 2000-12-05
Classification: F01N,F02D,Y02T

Abstract:
A method for injection duration correction in an internal combustion engine, which comprises:blowing secondary air into an exhaust tract upstream of a catalyst via a secondary-air system during a warm-up phase of an internal combustion engine;detecting a main-air mass flow present in an intake tract of the internal combustion engine and a secondary-air mass flow provided by the secondary-air system;carrying out an injection duration correction in dependence on the main-air mass flow, the secondary-air mass flow and a pilot control value for an air/fuel ratio;deducing a presence of a transient mode of the internal combustion engine from values of the main-air mass flow;correcting the secondary-air mass flow in the transient mode of the internal combustion engine, and calculating a deviation between a desired value, determined from a model for the secondary-air mass flow, and a detected actual value of the secondary-air mass flow; anddetermining a correction factor for the injection duration correction from a correction value for the secondary-air mass flow, the main-air mass flow and the pilot control value for the air/fuel ratio.