Abstract: Internal combustion engine air/fuel ratio control responsive to low voltage operating conditions of an electrical system maintains stable, precise air/fuel ratio conditions under electrical system fault conditions affecting operation of fuel control components including fuel pumps, fuel injectors, and drivers therefor. Electrical system operating voltage is monitored and when a voltage drop below a voltage threshold associated with reliable engine cylinder air/fuel ratio control is diagnosed, the air/fuel ratio smoothly transitions to a reduced engine performance operating mode which, at least for high engine output power requests, limits fueling and airflow to the engine cylinders to a level that may be accurately, reliably supported by the fuel control system components under their reduced electric drive signals. The reduced performance operating mode is maintained while the fault condition persists.

Abstract: A method of manufacturing an oval shaped catalytic converter that reduces the amount of material and number of parts that are required for permitting the catalytic converter to treat the exhaust gases of an internal combustion engine and also improves the structural durability of the converter for high temperature applications by maintaining a higher mat density along the minor axis of the converter housing.