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New Car Review: 2004 Volkswagen Passat GLS TDI Wagon


PHOTO (select to view enlarged photo)

DRIVING DOWN THE ROAD
WITH CAREY RUSS

You need the space and comfort of a mid-sized car or wagon, but you'd like better fuel economy. None of the currently-available hybrids are the right size, or you may be put off by hybrid complexity. What to do?

Think diesel. In particular, think Volkswagen Passat diesel. The TDI-PD sedan and wagon models are the newest additions to VW's successful Passat lineup and combine the space and comfort that have made the Passat popular with fuel economy not normally associated with a midsize car. I've just finished a week with a TDI wagon, and the average fuel consumption was 32 mpg for mostly city and secondary road driving. The hybrids I've driven did ten or fifteen mpg better, but were smaller and less comfortable. The Passat TDI's EPA highway rating is 38 mpg, and that does not seem overly optimistic.

And if ``diesel'' conjures images of a soot-spewing truck noisily rattling away, it's time to move into the 21st Century. Diesels are increasingly the preferred engines for cars, even luxury cars, in Europe, and Volkswagen is the number one diesel producer. Its Golf and Jetta TDI models, sold for a while here, have an enthusiastic following. Like the 1.9-liter engine found in those models, the new Passat TDI is turbocharged and intercooled, with fuel injected directly into each cylinder for maximum efficiency. But it's the next-generation TDI, with ``Pumpe Duse'' (PD) technology. Developed in conjunction with Robert Bosch Corporation, ``Pumpe Duse'' translates to ``unit injector.'' The injection pump, controls, and injector for each cylinder are in one unit, and there is one unit injector per cylinder. The injection pumps are driven off the camshaft. The design is extremely compact and precise. Fuel efficiency is related to the degree of atomization of the fuel before combustion. The higher the pressure of injection, the smaller the droplets of fuel, and the more complete the combustion - leading to increased power and decreased emissions. Early diesels, in the 1930s, injected fuel at 5,000 pounds per square inch (psi). The PD injectors inject fuel at over 29,000 psi, higher even than the more common common-rail diesel injection technology.

I've had three opportunities to drive TDI Passats. First were two laps around Northern California's hilly and twisting Sears Point Raceway during last year's Challenge Bibendum alternative-vehicle event. A European-spec sedan acquitted itself well, with no problem climbing the steep hills of the track. Then VW introduced the North American version in the rolling hills of Northern Virginia. Again, no problem with power, and a fine 33 mpg average on the ride and drive. Now I've just finished a week in the familiar territory of home, and have grown to like the TDI Passat even more. It's a rational and very functional solution to space, fuel consumption, and even pollution problems.

Diesel as a solution to air pollution? No, I'm not kidding. Diesels emit much less carbon dioxide than gasoline engines. They do emit more oxides of nitrogen and particulates (soot), but technology similar to the catalytic converters used by gasoline engines is being developed to scrub those pollutants from diesel tailpipes. However, similarly to the manner in which a catalytic converter is destroyed by leaded gasoline, the devices to thoroughly clean diesel exhaust need low-sulfur diesel fuel, which will not be available here until 2007. Modern diesel cars are clean enough for the EPA, but not for the California Air Resources Board, so the Passat TDI (and all other diesel cars) will not be available in California, New York, Massachusetts, Maine, or Vermont until the advent of low-sulfur diesel fuel.

APPEARANCE: Good, conservative design ages well. The Passat is a fine example. Since its debut in the 1998 model year, the current Passat has had only detail changes, including revised headlights and clear covers over the taillights. Auxiliary turn signals in the outside rear-view mirrors are new. The wagon's slightly angular rear styling blends well with the simple, gently-rounded front contours, and modest fender flares and discreet chrome trim give it a sport-luxury definition. Roof rails are standard on all wagons. Alloy wheels are standard on the GLS.

COMFORT: Passats are offered with interior trim from plain, with high-grade cloth and basic plastic to fancy, with leather and woodgrain accents. Like the exterior, the styling is tastefully conservative, with few changes over the years. A new and more useful center console was the major upgrade a while back. My test car had the basic interior specification, which meant grippy, cool cloth upholstery and no artificial wood trim. Comfortable seats offer good support, even on long drives, and the interior layout is simple and extremely functional. As is the norm for Volkswagen, the steering wheel is manually-adjustable for both tilt and reach. A tilt-and-slide moonroof is standard equipment in the GLS. Rear seat room is good, and the wagon's functional cargo space can be increased by flipping up either or both of the rear seat cushions and folding down the seatbacks. A long, flat load floor is the result, and unwieldy items like bicycles can fit inside easily.

SAFETY:Every 2004 VW Passat has four-wheel antilock disc brakes, a rigid body structure with front and rear crumple zones, front, front side, and front curtain air bags, and three-point safety belts for all occupants. .

ROADABILITY: On the road, the Passat's rigid chassis structure and supple tuning of the independent four-link front, torsion beam axle rear suspension gives a comfortable and well-controlled ride. Road and engine noise levels are low, and good underbody air management helps keep wind noise minimal. While not a sport wagon, the Passat TDI can be driven enthusiastically without complaint. .

PERFORMANCE: There are no complaints from the engine compartment for spirited driving, either. If your impression of diesels includes ``slow,'' think again. The Passat TDI's engine is quiet, smokeless, and hassle-free. If the outside temperature is above 40 degrees Fahrenheit, no pre-glow ignition is necessary. So there is no waiting for the glow plugs to warm before starting - just get in, turn the key, and go. There is no need for a long idle, either. Power statistics are 134 horsepower at 4,000 rpm and 246 lb-ft of torque at 2,000 rpm. Torque is what moves a vehicle, and diesels are excellent torque producers. The five-speed automatic suits the engine's broad torque curve well, and shifts smoothly. If more sporting driving is desired, merely place the shifter into ``Tiptronic'' (r) mode for manual shifts. The car is a little slow right off the line, but once the torque peak at 2000 rpm is reached, it moves quickly, and develops useable power past the relatively high power peak. A zero-to-60 time of 10.4 seconds is better than that of any current hybrid. Fuel economy is excellent at 32 mpg average for mostly city driving, and the engine is very quiet and unobtrusive from inside the car. Outside a muted diesel sound is audible - just enough to let anyone nearby know you won't be stopping for fuel any time soon. .

CONCLUSIONS: The Volkswagen Passat TDI will revise opinions of diesel-powered cars.

SPECIFICATIONS
2004 Volkswagen Passat GL TDI Wagon

Base Price		            $ 25,060
Price As Tested		            $ 26,240
Engine Type		            inline four-cylinder single overhead cam
			            8-valve turbocharged and intercooled 
			            direct-injection diesel
Engine Size		            2.0 liters / 120 cu. in.
Horsepower		            134 @ 4,000 rpm
Torque (lb-ft)		            247 @ 1,900 rpm
Transmission	            	    5-speed automatic with
		                       ``Tiptronic''(r) manual mode
Wheelbase / Length	            106.4 in. / 184.3 in.
Curb Weight		            3,519 lbs.
Pounds Per Horsepower               26.3
Fuel Capacity		            16.4 gal.
Fuel Requirement	            diesel
Tires			            P195/65 HR15 Continental Touring Contact
Brakes, front/rear         	    vented disc / solid disc, antilock standard
Suspension, front/rear	            independent four-link /
			            semi-independent torsion beam axle
Drivetrain	            	    front engine, front-wheel drive

PERFORMANCE
EPA Fuel Economy-miles per gallon   city / highway / observed 27 / 38 / 32                                             city / highway / observed 27 / 38 / 32
0 to 60 mph			    10.4  sec

OPTIONS AND CHARGES
Cold weather package - includes:
  heated front seats, front heated windshield washer nozzles	$ 325
Electronic Stabilization Program				$ 280
Destination charge						$ 575
PRICES, SPECS, COMPARAGRAPHS, FUEL USAGE