1998 Volkswagen Jetta TDI
"The Hassle-Free Diesel" by Keith Buglewicz
Note: This article was transcribed from an edition of European Car Magazine. Since the use of article's photos was not possible, I have substituted photos from the Internet and added TDI badges. Similarities to my own Jetta are coincidental.
[Back to Main TDI Page][Links][E-Mail Me]
I remember the first time I drove a Volkswagen Diesel. I was only 15 and not what you would call a worldly driver. The number of different vehicles I had driven up to that time could be counted on one hand. Yet, as naïve as I was, I knew that the Rabbit Diesel left much to be desired. Not only was it small, it made peculiar noises and smelled awful. The whole car shook with each beat of the motor. There was a thick cloud of black smoke following the little Rabbit wherever it went. Worst of all, it was cold-maple-syrup slow.
Despite all these flaws, Rabbit Diesels sold like crazy. Almost everyone has heard stories of buyers following transports full of the little oil-burners to Volkswagen dealerships. Customers overlooked their flaws for one simple reason: They used precious little fuel in a time when gas prices were spiraling out o sight.
Of course, we have no gas crisis today. With gasoline cheaper than bottled water, why would someone want to put up with a diesel? Sure, mileage is great, but what about the smell? Or the noise? Or waiting for the glow plugs to warm up?
Confronted with this attitude, it may seem crazy for Volkswagen to market a diesel. But the 1998 Jetta TDI bears little resemblance to its smoky forerunners. Twenty years of advancing the art of manufacturing diesels (driven by a strong European demand for them) has turned the TDI into a truly hassle-free deal. Not only does it get outstanding mileage (an EPA estimated 40 mpg city, 49 mpg highway; my lead foot averaged about 37 mpg), it does so with a minimum of fuss, never calling attention to its dieselness.
The heart of the vehicle, obviously, is the 1.9-liter, 90 -hp turbocharged diesel motor. Compared even to a modern gasoline engine, the TDI (Turbo Direct Injection) is quite sophisticated, with some features not expected in a $16,000 commuter-mobile.
Take, for example, the "drive by wire" throttle. A common feature found on many luxury cars, it is used in the TDI to precisely deliver the proper amount of fuel. It is also one of the measures that allow the TDI motor to do away completely with the pre-chamber normally found on diesel motors. The pre-chamber was used to ignite a small amount of fuel, which would then spread to the main combustion chamber where the remainder would be burned. Although effective a lighting off the relatively non-volatile diesel fuel, it was inefficient because of the heat loss from the initial combustion. This resulted in considerably less power than the engine would otherwise be capable of. The TDI uses a direct-injection fuel delivery system. Similar to a gasoline fuel-injection system, the direct-injection delivers fuel straight to the combustion chamber, where all of its energy can be used to create power for propulsion.
Assisting in the power department is a small turbocharger located on the back side of the engine. While only providing 5 lb of thrust, there is zero lag from the little intercooled turbo, and no noise either. All the driver feels is smoother, steady power, virtually from idle to about 500 rpm below the car's modest 4700-rpm redline.
A surprising amount of power, for that matter. Not only does the Jetta TDI have enough ponies to get out of its own way, it has plenty in reserve to dispel notions that diesel-powered cars are rolling chicanes. It isn't going to set land-speed records, but it isn't so slow that 0-60-mph times have to be measured with a sundial.
In fact, the TDI may be the first diesel on these shores that can actually be considered fun to drive. The TDI boasts lots of low-end torque, 149 ft-lb at only 1900 rpm, to be exact. That's just 24 less than the hairy-chested VR6, and 27 more than the standard gasoline-powered four banger. With shorter gearing in first through third than the standard four cylinder (although with a taller final-drive ratio), the TDI gets moving plenty quick.
Best of all, it does all this without calling attention to itself. There are no unpleasant smells emanating from the tailpipe (except when the car is first started in the morning), and the clatter from under the hood is well subdued at idle and unnoticeable at speed. You don't even have to warm up the glow plugs - the orange coil on the dash goes out almost instantaneously. About the only difficult part of owning a TDI would be finding a diesel-selling gas station in your area. But Volkswagen even thought of this, supplying a handy guide that gives the location of just about every diesel outlet in the country. When you get there, the reformulated diesel fuel used today is significantly less smelly than you may remember, but you might still want to wear a glove.
Aside from its fancy motor, the Jetta TDI is pretty much standard issue. The underpinnings hold no surprises to Volkswagen fans: MacPherson struts up front and a torsion beam axle with coil springs in the rear, both ends complemented with an 18mm anti-roll bar. Tires are skinny 195/60R-14 Goodyears that loose grip well before the chassis is through with them. As with most front drivers, understeer is the dominant handling characteristic, but it is well enough controlled in the Jetta that the driver can still be entertained. Of course, if you want to impress the neighbors, the Jetta will dutifully lift its inside rear wheel under hard cornering, as if to mark its territory in canine fashion.
On the road, the Jetta feels solid and tight. The engine is quiet at highway speed, and the steering feels direct and communicative. Small bumps are absorbed without commotion, but there is too much rebound on dips, with the car bouncing for several beats after passing over one. The tires tend to hunt out grooves in the road, but upgraded rubber would solve that nicely.
Inside, Volkswagen has bucked the trend toward cheap-feeling, hollow-sounding hard plastic trim. Virtually every surface has a slightly softer touch to it. Although the difference is subtle (think hard rubber versus hard plastic), it is still a step above some of its Asian and American competition. All the required amenities are there, too, with plush cloth seats, tilt steering wheel, cruise control, optional six disc CD changer in the trunk, and a generally ergonomic layout.
Quibbles are few: The shifter still feels a little floppy, and the overall design, inside and out, is showing its age. Considering our car had only 3,500 miles on it, I was disappointed to hear a little rattle at idle from behind the stereo, and an occasional body squeak from the left rear door.
Volkswagen fans won't have to wait long for the next Jetta. Along with the new Golf (already on sale in Europe), the Jetta's sleeker styling is an evolutionary step, but one that updates the car to the '90s and little beyond. As for the TDI, well, it's not quite the ultimate enthusiast's Volkswagen, despite some limited performance gear available from Neuspeed. But it is a real car, not a temporary crutch to help one limp through a gas crisis.
While this article is well-written and thorough, a TDI owner did not write it.
Please see "My 1998 Jetta TDI, An Owner's Point of View" for supplemental information to this article.
[Back to Main TDI Page][Links][E-Mail Me]