HOOD RIVER, Ore. -- A looped course, swooping into Oregon's picturesque Columbia River Gorge, shows off the Teutonic handling traits and gutsy attitude of a new edition of Volkswagen's Jetta compact notchback sedan outfitted with a turbocharged four-in-line engine which drinks "clean" diesel fuel.
Among automobile powerplants containing internal combustion chambers, the pressure-ignited heat engine named after German inventor Rudolf Diesel is considered most efficient for burning fuel and translating the resulting energy into linear movement.
The first passenger car powered by one of Diesel's engines -- the 260D from Mercedes-Benz -- came in 1936.
Following the Arab Oil Embargo of 1973-74, various cars in the American market employed a diesel-type engine.
Yet sluggish performance figures in combination with sooty emissions and obnoxious belching noises from those diesels soured the concept for consumers in the United States, and most automakers deleted diesel engines from passenger cars by 1989.
Now click your fast-forward switch to today's time zone and you'll find that engineering wizards at Volkswagen have developed a new generation of diesel engines which deliver surprisingly quick acceleration times but produce low exhaust emissions and superior fuel economy scores.
They're quiet too.
That leads us to the 2009 Jetta TDI, a new diesel-powered version of the Jetta sedan by Volkswagen that's street-legal in all 50 of the United States.
Here's the surprising revelation from our time in the driver's seat of a Jetta TDI: It delivers a neck-snapping kick each time you put your foot into the go-pedal.
Jetta TDI totes a 2.0-liter four-cylinder engine that burns ultra-low sulfur diesel (ULSD) fuel and employs a common-rail direct injection (CDI) fuel system with electronically controlled turbo-charging to enhance engine power and torque.
It feels vigorous and acts quickly, drawing on the full force of the engine's production of 140 hp peaking at 4000 rpm plus 236 lb-ft of torque spread across a band from 1750 to 2500 rpm.
Drop that short stick down a gear on the six-speed manual transmission version and that engine torque surges from the shift to higher rpms.
Or use the twin-clutch and six-speed DSG (Direct Shift Gearbox), a remarkable automated manual transmission.
In general, cars equipped with diesel engines achieve better fuel economy figures than do cars with gasoline engines due to the higher energy content of diesel fuel and the overall efficiency of a diesel engine.
For Jetta TDI, the federal Environmental Protection Agency sets the fuel economy numbers at 29 mpg City and 40 mpg Highway.
Then the Internal Revenue Service issued a certification letter affirming that TDI qualifies for an Advanced Lean Burn Technology Motor Vehicle federal income tax credit of $1,300.
That in effect amounts to a sweet discount off TDI's stock MSRP of $21,990.
The TDI Jetta is a dreamboat to drive.
Its body, constructed of high-strength steel rails and beefed-up body panels united by tight bonding techniques such as laser-welded seams, is a strong unibody framework that's incredibly stiff to resist torsional twisting when set to motion and forms a bedrock foundation to carry suspension and powertrain components.
Romp across pavement tar bumps and the independent suspension dribbles 16-inch 205/55 all-season tires in exacting up-down motions which mimic the taut ride quality of a sporty car.
In front, a MacPherson strut arrangement manages to negate that annoying wheel-jerking torque steer effect prevalent in the usual front-wheel-drive (FWD) vehicle.
In back, a four-link design acts to check body roll.
Brakes on TDI consist of large discs tied to smart electronic controls. The equipment includes an anti-lock brake system (ABS) with electronic brake pressure distribution (EBD) and hydraulic brake assistance (HBA), plus VW's anti-slip regulation (ASR) throttle checker.
All of these acronyms in electronic vehicle controllers are components of the electronic stabilization program (ESP) which is standard issue on every 2009 vehicle by Volkswagen.
Crisp styling for the exterior package of the TDI features a low nose and sloping hood with lines sweeping up to the canted windshield and over an arching roof.
Side roof pillars go dark to blend with the tinted windows and create the impression of a sleek coupe.
The brash face sports a chrome-encrusted grille sandwiched between corner headlamp clusters with air intake vents cut into the deep fascia.
Flanks show subtle bulges from flares around wheels and side skirts.
A blunt rump has twin-bulb taillight assemblies at back corners and the bumper is punctuated by an offset pair of exhaust pipes.
Climb aboard the new Jetta TDI and you'll discover a five-seat passenger compartment with more room than a car in the compact class should contain and more fine materials and fancy appointments than a car with affordable price points usually provides.
The layout pits a pair of bucket seats with center console in front and a broad and flat bench with three seat positions. There's a fold-out center armrest with pass-through door to the trunk and rear seatbacks that fold to expand the cargo capacity.
The trunk is huge for the class -- 16 cubic feet of stow space above a flat floor.
Seat upholstery consists of high-quality leatherette V-Tex with trimwork in chrome metal for door handles and leather wrapping the three-spoke steering wheel and parking brake lever.
Standards on the list of on-board gear include air conditioning, an anti-theft alarm system, power controls for windows and door locks and exterior mirrors, lots of air bags such as curtain-style air bags in headliners, and a premium audio kit with AM/FM/MP3 and six-disc CD changer.
Equipment options for the TDI range from a touch-screen navigation system with auxilliary multimedia connector (MDI) to backseat side air bags, a sunroof and 17-inch Avignon alloy wheels.