A catalyst (52) having an oxidization capability is provided in an exhaust passage. After a rich control for controlling the air/fuel ratio of a mixture formed in a combustion chamber (25) to be an air/fuel ratio richer than the stoichiometric air/fuel rat...

A control system for an internal combustion engine, which is capable of properly controlling both the temperature of an exhaust system and the air-fuel ratio of exhaust gases even when the control range of the air-fuel ratio of a combustion air-fuel mixtur...

The method involves selecting a value for lambda different from that defined for a sub-stoichiometric mode following transition from an overrun mode into the sub-stoichiometric mode for a defined period or a period determined by the signal of an oxygen-sen...

In a process to operate a direct fuel-injected engine with exhaust gases discharging to a NOx storage catalytic converter, the motor is operated with a homogenous stoichiometric air/fuel ratio as a stratified charge engine, or in a homogenous lean-burn mod...

A control apparatus is provided for eliminating a slippage in control timing between the input/output of a controlled object, even when the control object exhibits a relatively large dynamic characteristic such as a phase delay, a dead time, or the like, t...

The invention proposes that the frequency of unacceptable combustion incidents is monitored using known methods for detecting misfires. Depending on this the operating conditions in which operation with a lean mixture is restriced or prohibited.

An exhaust gas purifying system, which has a NOx purifying catalyst (22) disposed in an exhaust line (20) operative to increase a NOx conversion efficiency with a rise in catalyst temperature to a specific temperature at which the NOx purifying catalyst (2...

An exhaust control system for a cylinder fuel injection engine having cylinder injection injectors (15) directly injecting a fuel into combustion chambers (16) and a catalytic converter (19) provided in an exhaust passage (18) from said combustion chambers...