Volkswagen, breaking a 30-year tradition, has introduced a flexible-fuel version of the Polo with a new, gasoline-free cold-start system.

Ethanol-fueled cars have been around in Brazil since late 1979, and flexible-fuel gasoline/ethanol cars today account for 90 percent of local sales. But since their inception, these cars have been plagued by a sticking point: the tiny 0.7-liter gasoline reservoir up front that's necessary for cold starts.

Ethanol is hard to vaporize. The U.S. and Europe found a solution to this by blending gasoline with ethanol at a 15:85 ratio (hence the E85 label). But 30 years ago, the Brazilian energy authority took a different path by ruling in favor of E100 (pure ethanol) rather than E85, partly because average temperatures are higher in the Southern Hemisphere.

Above 57 degrees F, ethanol will vaporize and ignite normally. Below that, a small amount of gasoline must be injected in the intake manifold during cranking. This necessitates a rather awkward cold-start system under the hood consisting of a reservoir, an electric pump and one or two nozzles at the intake manifold level.

Honda was troubled in finding a suitable place for the system in the crowded Civic engine compartment when it introduced a flex-fuel version in 2007. The bizarre solution involved installing the system inside the front right fender, protected by a 5mm-thick naval steel structure to assure safety in accidents. The Fit followed, but for brand standardization purposes only, since it had the necessary under-hood space. But all this is history now.

VW last week introduced the 102-horsepower 1.6-liter Polo with E-Flex badge, which denotes the installation of a Flex Start system. It's a joint development with Bosch, consisting of a few measures to render possible cold starts at temperatures down to 32 degrees F, without any gasoline aid.

The system's main feature is the special fuel rail that heats the ethanol fuel, making it easier to vaporize. A control unit monitors temperature conditions and triggers the heating as soon as the driver's door is unlocked. Monitoring continues through the warming-up phase, thus assuring ethanol temperature high enough for good vaporization.

The Polo 1.6-liter E-Flex special series is the only VW so equipped thus far and retails for $19,895, about 15 percent over the regular Polo 1.6, yet compensated by the addition of air-conditioning, power steering, power windows, central locking, foglamps and a CD player with MP3 and USB connectivity, among other amenities.