Repair manual

SULEV 2.0L TFSI Engine
32
Exhaust Turbocharger
The turbocharger used on SULEV emission level engines
is made of cast steel, and not cast iron. Cast steel
provides excellent long-term stability. In addition, the
components heat up more quickly after engine start-up
because they have thinner walls.
Cast steel also allows the oxygen sensor to be positioned
inside the turbine housing. This is necessary to ensure
the rapid availability of the sensor.
Both air flow and catalytic converter inflow have been
greatly improved, reducing the exhaust gas back-
pressure upstream of the turbine. Reduced back-pressure
means less possibility of turbo-lag while also increasing
fuel economy.
Cast Steel
Integral Module
Heated Oxygen Sensor
G39 Upstream of Primary
Catalytic Converter
(broadband oxygen
sensor in the
integral module)
Wastegate
Configuration