heengineisinthecorrespondingengineloadandspeedranges-therearenoexhaustemissionfaultsinthesystem-thecoolanttemperatureisabove50°C-theNOxsensorisready,and-thetemperatureoftheNOxstoragecatalystisbetween250°Cand500°CIftheaboveconditionsaremet,theenginemanagementsystemcanchangeovertostratifiedchargemode.IntakeprocessInstratifiedchargemode,thethrottlevalveisopenedaswideaspossibleinordertominimisethrottlelosses.ThrottlevalveTheintakemanifoldflapclosesthelowerductinthecylinderhead.TheintakeairflowsatafasterIntakemanifoldrateandtumblesintothecylindersviatheupperflapduct.pletelyasacertainvacuummustalwaysbepresentduetotheactivatedcharcoalcanistersystemandexhaustgasrecirculation.AirflowInthecylinder,thetumblemotionoftheairisincreasedbythespecialshapeofthepistoncrown.TumbleairAirflowFlowrecess253_03810