In unveiling the Avante Diesel last week, Hyundai Motor broke an unwritten rule in the automotive industry: A carmaker never elaborates on its direct competition.

“During the development of the diesel model, we carried out comparison tests with the Volkswagen Golf,” said Jeong Byung-kwon, Hyundai’s chief of compact vehicles, during the launching event.

“While Volkswagen’s BlueMotion focused more on better fuel ratings, we made efforts to improve the noise issue and performance as well. We feel confident the Avante Diesel has an edge in the race.”

The diesel-powered version of the compact, known as the Elantra in the U.S., comes at a time when Hyundai has lost some of its edge in the Korean car market. This is especially true for lucrative high-end cars, where it lost ground to German premium brands.

In the last five years, the combined share of Hyundai and its affiliate Kia Motors in the overall automobile market, which once reached 86 percent, has fallen to about 70 percent, even though competitors still complain about their dominance.

Another issue is diesel models. While the Korean duo ignored the marketability of diesel cars, which were seen as noisy and dirty, foreign brands moved quickly to introduce smoother, more efficient and more powerful machines.

Putting the 1.6-liter diesel engine on its bread-and-butter compact seems the desperate but logical outcome of Hyundai’s years of difficulty.

While driving on the almost empty highway connecting Seoul and Chuncheon, the Avante Diesel did little to wow me with its dynamic capabilities.

But living up to the car’s name ― the best-selling sub-compact since its launch in 1990 ― the ride of the diesel model was smooth and comfortable. The steering was also quick and accurate.

What the carmaker stressed was the decreased engine sound. When the engine idles, the noise was 43 decibels for diesel, 40 for gasoline. But at high speeds, the figures showed almost no difference with 53 and 52.

The carmaker needs to refine the quality of the engine sound ― not just for the Avante but also for Hyundai-brand cars overall ― if it hopes to appeal to Korean consumers who are developing tastes for the more luxurious roaring of German premium cars.

The fuel rating of 16.2 kilometers per liter is no surprise compared to its gasoline model’s 14.2 and the Golf 1.6 TDI’s 18.9.

The budget compact is also equipped with a lengthy list of convenient features such as heated or cooled driver and passenger seats, a cooling storage box, keyless ignition and a rearview camera.

If the Avante, priced at 17.45 million won to 20.9 million won, only competes with the 29.9 million won Golf, its price tag looks quite promising.

But the sad truth is the hot-selling Golf is more aimed at competing with low-end BMW or Mercedes cars, not its Korean peer.

By Lee Ji-yoon (jylee@heraldcorp.com)