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Home >> Volvo >> 2009 >> XC90 R-Design, FWD >> Repair and Diagnosis >> Engine Performance >> System >> Electronic Modules - Design And Function >> Engine Control Module (ECM) (B8444S; 2005-2011) >> Function >> Variable Intake System
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Variable Intake System

Fig 1: View of Variable Intake System Components
GLL149975Courtesy of VOLVO CARS CORPORATION

The variable intake system components consist mainly of:

  1. Vacuum tank
  2. Valve for variable intake
  3. Vacuum motor
  4. Throttle discs

In order to maintain a high volume of intake air at different engine speeds (RPM) and engine loads, B8444S is equipped with the Variable Intake System. The Variable Intake System divides drawn in air into two volumes. The engine control module (ECM) then regulates the air flow between these volumes using dampers in order to achieve the optimum air flow at specific operating temperatures.

The vacuum from the engine is stored in a vacuum tank (1). The vacuum is then guided to the vacuum motor (3) using the variable intake valves (2). The vacuum motor affects the damper in the intake system.

The variable intake valve is controlled by the engine control module (ECM) (4/46).

The variable intake valve can be activated and the variable intake function can be diagnosed by the engine control module (ECM).