Audi 2009 A4 allroad, Pricing And Specification Manual, Page: 11 / 82

12
Engines
Petrol
All A4 petrol engines feature FSI direct-injection – a unique
Audi technology originally developed for the Le Mans 24-hour
endurance race to deliver increased power and torque, as well
as enhanced fuel efficiency. Precisely the right amount of fuel
and air are injected into the combustion chambers, enabling
the engine to ‘breathe’ more easily. The result – reduced heat-
loss and increased output, with around a 15% reduction in fuel
consumption and significantly lower exhaust emissions.
Diesel
All diesel engines from Audi are known as TDI. This impressive
technology was originally pioneered by Audi in 1989, marking a
departure from the noisy, fuel-thirsty diesel engines of the past.
Like its FSI petrol counterpart, the TDI diesel engine is designed
for power, performance, low fuel consumption and reduced CO
2
emissions. The A4 TDI engines are based on the common rail
system. Here, fuel is stored and kept at constant pressures of
up to 1,600 bar, ready to feed a series of highly accurate piezo
injectors, which control the rate and point of injection.