(DE19935826-A1)   NOVELTY - The method involves changing the engine operating mode from a lean fuel/air mix to a rich fuel/air mix and then using a supplemental torque apparatus (34) that is operatively connected to the engine to convert a proportion of the engine torque, which is increased by the change in engine operating mode, into energy which can be stored and then later controllably released.    USE - For controlling torque in direct injection engines that have a lean NOx trap in the exhaust system and a supplemental torque apparatus operatively connected to the engine.    ADVANTAGE - The method enables lean NOx tanks to be purged while avoiding any undesirable engine torque disturbances. A supplemental torque apparatus is a faster actuator than using the electronic throttle, has a direct influence on engine torque and is more suitable for torque mitigation than using the throttle. Engine operation at higher loads is more efficient, at least for homogenous operation during the purge mode, than it would be using the throttle to control torque and efficiency is also gained due to reduced pumping losses when the throttle is open. The extra energy generated during the purge mode is stored for future use during the lean mode and the use of a supplemental torque apparatus for torque management frees up spark time for emission control.    (US6079204-A)   NOVELTY - The method involves changing the engine operating mode from a lean fuel/air mix to a rich fuel/air mix and then using a supplemental torque apparatus (34) that is operatively connected to the engine to convert a proportion of the engine torque, which is increased by the change in engine operating mode, into energy which can be stored and then later controllably released.    USE - For controlling torque in direct injection engines that have a lean NOx trap in the exhaust system and a supplemental torque apparatus operatively connected to the engine.    ADVANTAGE - The method enables lean NOx tanks to be purged while avoiding any undesirable engine torque disturbances. A supplemental torque apparatus is a faster actuator than using the electronic throttle, has a direct influence on engine torque and is more suitable for torque mitigation than using the throttle. Engine operation at higher loads is more efficient, at least for homogenous operation during the purge mode, than it would be using the throttle to control torque and efficiency is also gained due to reduced pumping losses when the throttle is open. The extra energy generated during the purge mode is stored for future use during the lean mode and the use of a supplemental torque apparatus for torque management frees up spark time for emission control.