Porsche CAYENNE Brochure page 51

The secret of performance?
Efficiency.
Exhaust emissions. standard as well as LEV2 – LEV
(Cayenne and Cayenne Turbo)
The Cayenne models are all and LEV2 – ULEV (Cayenne S
equipped with the very latest and Cayenne GTS) regulations
emissions technologies. As a in the United States. Whatever
result, they comply with both the the class, every Porsche
stringent EU4 exhaust emissions combines high performance
with only moderate emissions.
On the Cayenne models, this is
achieved using an advanced
engine concept featuring direct
fuel injection, VarioCam Plus
(V8 engines) or variable valve
timing (V6 Cayenne) as well as
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OBD II on-board diagnostics. The reduced sooner when starting
key components, however, are the from cold.
primary and secondary catalytic
converters on the twin exhaust Another important feature is
tracts. Each catalyst has a rapid the use of twin oxygen-sensor
warm-up cycle so emissions are circuits. Each bank of cylinders
has a separate control system
which the engine management
system uses to establish the
optimum air/fuel mix and monitor
the efficiency of the catalytic
converters.
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Environment