It has taken more than 30 years for mainstream consumers to forget the gutless, unreliable, smoke-belching, oil-burning cars of the ’70s and ’80s, but diesel is finally a viable option in light-duty vehicles again. Due to advances in technologies that have resulted in wider acceptability amongst consumers, “diesel” is no longer a dirty word—or fuel. Today’s crop of clean-diesel vehicles are hitting their stride and getting a second shot at going head-to-head with their gasoline-powered counterparts.
Much of these inroads and changes in perception can be traced directly back to one company: Volkswagen. VW introduced its first modern Turbocharged Direct Injection (TDI) engine to America in 1996. This 1.9L made only 90 hp but was extremely driveable, thanks to 149 lb-ft of torque.
The 2.0L DOHC I-4 TDI engine uses piezo injectors that fire multiple injections per cycle,
Fast-forward to today, when the current 2.0L I-4 TDI engine produces 140 hp and 236 lb-ft of torque and is available in seven Volkswagen models. The 16-valve, DOHC engine uses turbocharging, direct-injection, and common-rail technology, while passing today’s strict emissions standards without having to rely on selective catalytic reduction (urea). However, the engine does use an innovative low- and high-pressure EGR system that runs cleaned and cooled exhaust gas (post-DPF) through the turbocharger. The turbo, which is a specialized unit from BorgWarner, has a nano-coated compressor wheel and housing that allows it to survive the hazards of high temps and exhaust acidity that come with this exclusive EGR setup.
Another unique property of VW’s 2.0L TDI engine is the use of individual cylinder pressure sensors in the glow plugs. These sensors feed information to the ECU to adjust air intake, fuel injection, and EGR, among other parameters, to ensure each cylinder has the same controlled combustion. The sensors also allow for the implementation of consistently higher combustion pressures for improved performance and efficiency.
Comfortable and well laid out, the Passat’s interior is a great place to tick off the mile
Volkswagen’s TDI models offer a mix of fuel economy and value, untouched by any other manufacturer. Take, for example, the subject of our road test, a Tennessee-assembled ’13 VW Passat TDI SE with an as-tested price of $26,225, just a $2,280 premium over a similarly equipped gas model. Our SE arrived with a six-speed manual transmission and was well equipped with power windows, doors, and locks; A/C; heated seats; and a decent stereo. The Passat’s interior is trimmed nicely for the price, with soft-touch padding in all the right places, and a generally upscale feel. The price includes an EPA-estimated 31 mpg city and 43 mpg highway, beating the base Passat’s 2.5L gasoline engine by 9 mpg city and 11 mpg highway.
After spending a week behind the wheel of the Passat, we think the best thing about it might just be how normal it is. To us, there is no compromise. The Passat isn’t small, it doesn’t look weird, and there aren’t any computers or nannies to detract from the driving experience. In fact, the Passat is so normal that you can just get in and drive with no special procedures to follow. Sit down, depress the clutch, turn the key, and go. In most conditions, the fast-light engine doesn’t even require a wait for the glow plugs to warm.
If we gave an award for trunk space, the Passat would probably walk away with a trophy.
Aside from the “TDI” badge on the trunk lid, there is very little that distinguishes the diesel-powered Passat from its gasoline-powered siblings. On startup and at idle, there is some increased NVH compared to a gas engine, but nothing disconcerting. The little four-banger provides a welcomed punch off the line with almost no turbo lag and exhibits an endearing snarl on acceleration.
Once underway, the engine settles down into a quiet cruise. At 75 mph, we had no problem climbing steep grades in Sixth gear, and the fat torque band can easily be accessed with the right foot—no downshift required. Of course, downshifting keeps the engine on the boil, and the little four has plenty of confidence-inspiring power in reserve for passing. The tach redlines at 5,000 rpm, although we found the quick-revving engine ran out of steam just north of 4,500 rpm.
For those who like to shift for themselves, the manual transmission is a good match for the engine and adds a dose of fun to a normally boring vehicle class. While we did find the shifter to be less precise than what we expected from a German car, we were able to adapt quickly to the feel, and the clutch and shifter became second nature. Curiously, the manual is only available on the SE, so if you want a higher-contented car, you’ll be assigned the six-speed DSG automatic gearbox.
From backroads to freeways, we enjoyed the Passat’s chassis. The structure is tight, the electrically assisted power steering didn’t feel overly boosted, and the brakes were above average in performance. While German cars are typically tuned more for windy-road performance, the Passat is clearly skewed more toward cruising the Interstate than corner bombing. This better matches the 3,400-pound Passat’s relaxed character, as well as its intended audience.
Rear seat passengers benefit from the Passat’s exceptional legroom.
During the course of 1,633 mostly highway miles, we averaged 43.7 mpg, with a best tank of 44.76 mpg. This beats even the EPA estimates, which is something we don’t experience often. For more mileage-conscious drivers, we bet there’s more mileage to be found, as our logbook noted the trip computer indicated more than 50 mpg on a stretch from Vegas to L.A. With a quiet, incredibly supple ride, and comfortable seats, one could easily take advantage of the Passat’s more than 750-mile range in one sitting—as long as there wasn’t a Big Gulp in the cupholder.
Overall, the Passat TDI exceeded our expectations for comfort and economy, while still mixing in some enjoyment of the drive. The only real missteps that are worth mentioning are pedals that are positioned too close together for our size 10s, and the front row’s inboard-mounted seating position. While the Passat is a relatively wide car, the front seats are mounted inboard in relation to the center console and door. What this means is that your right side is right up against the console and passenger’s shoulder, while your left side has plenty of breathing room against the door. Fortunately, the steering wheel is centered on the seat, so despite the odd position, the driver is properly aligned with the controls.
That being said, the Passat does everything you’d want from a midsized sedan—and does it well. The TDI engine has plenty of power and room for the whole family yet is efficient enough to be your daily commuter. It is a no-compromise car that merges incredible fuel economy and value pricing, making us wonder why anyone would ever want to pay more for the added complexity and dubious mileage benefit of a hybrid. We are glad there are clean-diesel cars out there that are this good, because it shows the rest of the driving population that diesel no longer has to be our dirty little secret.
Vehicle model: 2013 VW Passat TDI SE
Base price: $26,225
Engine type: 2.0L I-4
Valvetrain: DOHC, four valves per cylinder
Aspiration: Turbocharged, intercooled
Mfg.’s hp at rpm: 140 hp at 4,000 rpm
Mfg.’s torque at rpm: 236 lb-ft at 1,750 rpm
Transmission: Six-speed manual
Axle ratio: 3.68 (Final I), 2.92 (Final II)
Suspension (f/r): Strut-type with lower control arms, coil springs, telescopic dampers, anti-roll bar/multilink with coil springs, telescopic dampers, anti-roll bar
Steering: Electrically assisted rack and pinion
Brakes (f/r): 12.3x1.0-inch vented discs/10.7x0.4-inch solid discs
Wheels/Tires: 17x7-inch aluminum/215/55R17 Continental ContiProContact
Curb weight: 3,393 pounds
Max payload capacity: 1,237 pounds
Fuel capacity: 18.5 gallons
EPA city/hwy mileage estimates: 31/43 mpg
Observed fuel economy: 43.78 mpg
We like: Torquey, quick-revving engine, comfy ride, plenty of room
We’d change: Driver’s seating position, crowded pedals
We say: No other car has this mix of size, value, and fuel efficiency for the price