German Car Zone

This Diesel Runs Four Rings Around Gasoline

Full disclosure: The 2009 Audi Q7 3.0 TDI clean diesel we describe here doesn't yet exist — sort of.
Don't get us wrong. Audi is committed to selling an Audi Q7 3.0 TDI with the very same fuel-efficient clean diesel powertrain, and it affirms that the vehicle will appear in showrooms during 2009. But it isn't yet clear whether the first examples of the Audi Q7 TDI will be officially homologated as 2009 or 2010 models.
Ah, technicalities.
Mileage Marathon
To us it matters not. We're cruising down California Highway 101 in a living, breathing preproduction example of a 2009 Audi Q7 3.0 TDI, nearing the finish of something called the Audi Mileage Marathon, a fuel economy competition Audi cooked up to show Americans the potential of the company's diesel engines.
Others in our group are driving TDI-powered A3s, A4s and Q5s — there's even a diesel-powered Audi TT coupe in the convoy. But those of us in Audi Q7 SUVs are the only ones competing in TDIs equipped with Audi's so-called ultralow emissions system that uses the increasingly familiar AdBlue urea solution that makes a diesel engine emissions-compliant in all 50 states.
The 1,000-mile route hasn't been easy. We joined the convoy in Las Vegas, where narrow two-lane roads descended below sea level into Death Valley, before climbing unsteadily to 7,500 feet for the night. From there we topped 9,945-foot-high Tioga pass on our way into Yosemite National Park. Day Two ended in the sleepy seaside town of Monterey, California.

Full article:edmunds

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