1980-02-01

Development of Closed Loop Secondary Air Control Three-Way Catalyst System 800399

The three-way catalyst system using a carburetor still needs a lot of improvement for meeting emission standards of U.S. for 1981, California for 1983, and Japanese for 1978. In order to improve air fuel ratio control capability of a carburetor three-way catalyst system, Toyota has developed a closed loop secondary air control system. In this system air fuel ratio is controlled not in the induction but in the exhaust. The short control loop of this system provides high air-fuel ratio oscillation frequency and rapid correction ability for maintaining the exhaust air-fuel ratio at stoichiometric. This gives the system a higher conversion efficiency. This paper describes the performance characteristics and an analysis of the system with regards to emission, driveability and fuel economy.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Energy Conservation with Increased Compression Ratio and Electronic Knock Control

790173

View Details

TECHNICAL PAPER

Study of Ceramic Catalyst Optimization for Emission Purification Efficiency

940784

View Details

TECHNICAL PAPER

Effect of Energy and Emission Constraints on Compression Ratio

760826

View Details

X