4-Cylinder Engines

The throttle valve housing is required to increase the amount of EGR in partial load range. Outside diameter of throttle valve housing is designed so that in its closed position an annular cross-section remains open. This allows the engine to idle smoothly at high altitudes with air conditioning on and power steering activated.

The lower half of housing is provided with guide vanes. These vanes ensure complete mixing of intake air and recirculated exhaust gas, so that each cylinder is provided with same quantity of exhaust gas.