FRANKFURT — Mitsubishi Motors Corp. is emphasizing its gasoline direct-injection (GDI) engine technology in its approach to producing a hybrid vehicle.

The company unveiled the concept Smart Utility Wagon (SUW) Advance at the recent Frankfurt auto show. The SUW uses a 1.5L GDI engine already in production but combines it with a small integral motor-generator and lithium-ion battery.

Mitsubishi's SUW Advance would challenge the Toyota Prius and Honda Insight. The car gets 3.6L/100 km (65 mpg), close to meeting the European goal of 3L/100 km (78 mpg).

A continuously variable transmission is mated to the 105-hp engine. Regenerative braking helps keep the battery topped off. The vehicle runs using two methods — a power mode, which makes the engine's power available, and a normal mode, which emphasizes fuel economy. If the lithium battery's charge is low, the car automatically chooses the ultra-lean combustion mode.

By relying more on its GDI technology, Mitsubishi says the cost of adding a smaller electric hybrid drive is not prohibitive. The SUW Advance weighs 980 kg (2,160 lbs.), thanks to aluminum in the hood, doors and suspension and lightweight resin for most body panels, including the bumper and fenders.

The company also has a companion vehicle, the three-door SUW Compact, which uses a new version of a GDI engine to achieve fuel economy of 4.5L/100 km (52 mpg).

The SUW Compact uses an automatic shut-off system that stops the engine at traffic lights and restarts it instantly when the driver accelerates. With additional tuning, says Mitsubishi, this might reach the 3L/100 km (78 mpg) standard.