Minimizing the Hydrocarbon Emission of a Spark-Ignited Engine at Cold Condition and Non-Stationary Operation

This paper presents a method that enables a significant reduction of the hydrocarbon massemission and other pollutants of the exhaust gas from the most popular type of engine used for passenger cars: The four-stroke, spark ignited piston engine.

The method is based on influencing only the internal process by a sophisticated concept of motor-controlling. The optimized parameters are A/F-ratio and timing of heat release. Any further devices concerning ignition system, injection system, exhaust system or sensors are not required.

The method is proven at cold condition and non-stationary operation. The tests have been carried out on a close loop controlled engine teststand that is able to simulate a realistic driving curve.

The method is practicable even and specially soon after the start, and it can be optimized in combination with the threeway-catalyst.