Back to the future: an engine maker transforms old technology in order to grow in Brazil.

The 450-year-old city of Silo Paulo will soon get the chance to recover the greenery it has lost over time. The city's 11 million inhabitants drive 5.6 million vehicles around the city. Of that total, nearly 5% run on diesel, including trucks and buses, which belch out daily a suffocating black smoke.

The resulting black cloud is one of the main pollutants of Brazil's largest metropolis. Data provided by the government's environmental health organization Cetesb shows declines in the concentration of pollution in 2003 compared to previous years. Nevertheless, "about 65% of the fleet remains outside acceptable standards," says Renato Ricardo Antonio Linke, the director of automotive engineering and certification for Cetesb.

A program to reduce air pollution, known as Proconve, cut emissions by 97% in new vehicles; another program, called improved maintenance for diesel-burning vehicles (PMMVD), decreased the number of these heavy motors failing to meet standards among used vehicles. Non-compliance fell to 5.8% in 2003 from 45% in 1995, according to Linke.

Procovne was launched by Brazil's National Council for the Environment, the federal body that oversees environmental policies. The PMMVD appeared in 1998 as a group effort by Cetesb, the Auto Repair Workers Union (Sindirepa), which represents independent auto mechanics, and the Automotive Quality Institute, a private, not-for-profit organization. According to Antonio Gaspar de Oliveira, Sindirepa's technical director, the program systematizes and sets up standards for services that regulate motor vehicles. "It certifies the condition of the motors in old vehicles, leading their owners to adopt a preventative and corrective stance," Oliveira says.

It was precisely in 1998 that the automotive industry introduced electronic motorization in diesel engines. The increasingly sophisticated technology reduces the pollution produced by commercial vehicles. However, MWM, a Sao Paulo manufacturer of diesel engines, went against the market trend toward technology.

The company instead transformed its old, four-cylinder engine into a new propulsion motor, an engine known as the MWM 4.10TCA Euro 3. It's an excellent alternative for the light trucks market--vehicles that carry seven to eight tons--because it's a lot cheaper than an electronic engine and because it meets European emissions standards. "Power and fuel efficiency aren't priorities in these segments focused on price," says Jose Eduardo Luzzi, MWM's executive director for sales and marketing.

Such technologies are going to accelerate the fight against air pollution. MWM, which posted sales of US$334 million in 2004, also makes electronic lines equal to the latest, top-of-the-line engines. They're more powerful, but they're also a lot more expensive. High pressure. The cost affects not only the motor. An electronic engine requires even more sophisticated electronic sensors. "The difference in price can vary from 7% to 10%, for example, for pick-ups, and by up to 30% for a heavy truck," says Luzzi. "In these engines, everything is thought about in function of an electronic fuel-injection system controlled at very high pressures, but not everyone is willing to pay for that new technology," says Guilherme Ebeling, MWM's head development and testing engineer.

The new Euro 3 is already attracting the attention of some heavy hitters. Volkswagen Trucks and Buses has been the first to embrace the idea. By law, 100% of new vehicles produced must meet Procovne standards beginning in 2006. Any automaker failing to respect that guideline can be forced out of the market.

At the end of the first quarter of this year, Volkswagen had reached barely 5%. The German automaker must reach that goal, precisely because it is the leader in light truck sales, with 35% of the market. "As the electronic motor makes our vehicles more expensive, over the course of the year we are going to offer that alternative in our 8.120 line," says Ricardo Alouche, Volkswagen's executive director of sales.