Audi's Diesels Run Rings Around Gas Variants

Think diesel, and three words may come to mind: Dirty, slow and unreliable.

Audi Auto Group wants to change this perception with its latest fleet of diesels, but it may be hard to win over a U.S. market familiar with large buses, trucks and old European imports that chugged along noisily emitting a thick, dark cloud of emissions.

Alternative energy vehicles have become the new trend, with cars like the Prius selling faster than Japan-based Toyota (TM) can build them. But even though hybrids are a respectable option, many European manufacturers already have proven technology within their diesel fleets.

Take Audi, for example, which by building fun-to-drive vehicles with robust miles-per-gallon numbers and uncompromised performance has created a compelling argument for new diesel technology.

Audi's A4 3.0 TDI reportedly averages more than 37 miles per gallon.

Through the lowering of harmful pollutants, diesels are Audi's answer to the short-term energy problem. The facts do not lie.

Turbo Direct Injection engineer Zaccheo Giovanni Pamio said the TDI engine uses "the most fuel-efficient technology in the world."

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Pamio says Audi's fleet uses 30% less fuel on average than it did in 1995, suggesting that TDI engines are the root of this turnaround.