Interest Popular Mechanics article.. but one of the things I noticed, is that their driving techniques:
Since fuel economy is so dependent on driving style, we accelerated as smoothly and consistently as possible in both tests. Our general rule was to accelerate from each stop with just enough throttle to be as quick as the slowest car leaving the light. This, we believe, best approximates the driving style that an average consumer would adopt with fuel economy as a main priority.
actually worked against the Jetta TDI. With turbocharged vehicles, efficiency goes up with boost pressure. Boost effectively increases the compression ratio of the engine (by increasing working pressures). If you feather the pedal on the Jetta TDI, the turbo never spools up.
How about testing the BMW 335d… !!
Should add a mileage category for mountain driving .. up to Big Bear, Laguna.. those types of areas ;-P
