Matching the fun is high mileage. From 238 miles of city and highway driving (about 60 and 40 percent, respectively), I averaged about 28 miles per gallon, all the more impressive considering the frosty weather still hugging the Northeast. On the highway, the trip computer - which unfortunately resets itself at every startup - was showing 40-plus miles per gallon. Many TDI owners, I'm told, boast numbers well over the official EPA 29/40 rating (with a light foot, 50 miles per gallon might not be out of the question).

A Scottish man in South Boston saw the big "TDI" decals on the Jetta and remarked how popular diesels were in his home country. "I guess you guys just like gas," he said. We sure do, but our distaste for diesel is changing. Since 2007, the EPA began a nationwide rollout of ultra-low sulfur diesel, which at 15 parts per million is a 97 percent reduction from standard diesel. It's widely available but not mandatory until 2010, so if you can't see a label for "ULSD," move on.

The TDI isn't as tolerant of lower-grade fuel like that of a gasoline-powered car. The catalytic converter is specially designed to burn off harmful nitrogen oxide emissions without additives (like the urea-based BlueTec system in Mercedes-Benz vehicles), and the particulate filters attached to the exhaust would quickly get clogged with the heavier soot from traditional diesel.

There's an occasional whiff of sulfur when the Jetta idles for a long time, but there's no smoke even during a cold start. Mild clatter fades as the engine warms, and then it becomes unnoticeable. If diesel was a buck-fifty a gallon now, this car would be topping the sales charts.

Unfortunately, diesel pump prices aren't likely to come down, thanks to reduced diesel refinery capacity and the higher cost of removing sulfur (and other reasons that would bring this story to a tangent). I filled up at a Hess station near the Globe for $2.35 per gallon, 46 cents higher than regular unleaded. But the TDI's $22,270 base price is just $2,175 more than the similarly-equipped SE. Factor in a $1,300 federal tax credit, and the difference comes to $875. That's less than typical hybrid premiums, especially for models like the Prius which are no longer eligible for IRS tax credits (a silly, numbskull rule).

The Jetta's conservative styling is offset by a handsome chrome fascia, but there's not much else that calls out the body in traffic. The interior comes off as a bit austere, but everything is simple, easy to find, illuminated, and clicks and presses with a fine, weighted touch.

Gripping the three-spoke steering wheel around turns is where the Jetta stands out. Moderately light at low speed, the wheel tightens with authority under cornering loads, and body roll is well-controlled. The brakes are equally strong, but the pedal feels too soft, which doesn't inspire driver confidence. Our tester had a little over 6,000 miles, so perhaps some other rabid journalist had been mashing the brakes into mush.

If you don't mind the diesel premium, the Jetta TDI is a fuel-efficient bargain that won't drain your enthusiasm for driving. But whenever you get sick of paying high pump prices, you can always join other savvy TDI owners in evading the IRS and filling up with used restaurant cooking oil.

Read part 1 of our drive in the 2009 Volkswagen Jetta TDI here.