Charge Air Ducting And Boost Pressure Control - Volkswagen 2004 Jetta Introduction Manual

Charge Air Ducting and Boost Pressure
Control
The boost pressure and intake pressure are
converted to control pressure by the pulse
width modulated Wastegate Bypass
Regulator Valve N75. Control pressure acts
on the pressure unit that actuates the
wastegate flap. The wastegate flap opens a
bypass and allows some of the exhaust
gases to flow past the turbine wheel into
the exhaust system. This control system
regulates the turbine speed and sets the
maximum boost pressure.
Wastegate Bypass
Regulator Valve N75
Pressure Unit
Turbocharger
Recirculating Valve
N249
If the control system fails, the
boost pressure acts directly on
the pressure unit. The increased
spring pressure reduces
maximum boost down to
minimum boost.
Wastegate
Brake Booster Servo
Vacuum Pump
Charge Air Cooler
332_011
Engines
Water Connection
Evaporative Emission
(EVAP) Canister Purge
Regulator Valve N80
Oil Filter
Module
43