VW 1.0 TGI dual-fuel engine

Volkswagen will be heading into the 38th Vienna Motor Symposium this year with a duo of new engines: an upgraded 1.5 litre, turbocharged TSI Evo petrol engine and a new 1.0 litre turbocharged engine which can run on either petrol or compressed natural gas.

The 1.5 litre turbocharged petrol engine which will debut in the upcoming Volkswagen Golf TSI Bluemotion will form part of a micro hybrid system, which can shut the engine off completely when the vehicle is coasting, which is possible at speeds of up to 130 km/h. Volkswagen describes this as having “hybrid-style characteristics.”

The 1.5 litre unit will be mated with the DQ200 seven-speed dual-clutch automatic gearbox, along with a lithium-ion battery added to the vehicle’s 12-volt electrical architecture for powering the vehicle’s electronics when it is coasting. Thus equipped, the system provides an improvement in fuel efficiency by up to 0.4 L/100 km, according to Volkswagen.

A Q-diode regulates the flow of current between the litihium-ion and lead-acid batteries in the car. When the internal combustion engine is restarted, it can be done so via several ways: by the starter motor, via the clutch (bump starting), or with a combination of both.

VW e-Golf high-voltage battery system

Next is the 1.0 litre TGI dual-fuel engine, which produces 88 hp. When running on natural gas, the 1.0 TGI engine is particularly low on CO2 and NOx particulate emissions, according to Volkswagen. Key to the TGI engine’s efficiency is the “optimum conversion of methane in the exhaust gas.”

A lambda split process was developed in order to quicken the warming up of the catalytic converter. Under low loads, two cylinders are fired with a rich fuel mixture while one cylinder is ignited with a lean fuel mixture. Along with electric heating, the regulating function is taken up within 10 seconds of a cold start, even if the exhaust system still contains a certain amount of condensation, Volkswagen explained.

The Wolfsburg-based automaker will also be showcasing its electric vehicle architecture at the Vienna Symposium, and says its first new all-electric model will make its debut in 2020. “The all-electric architecture combines local zero-emission driving with superb long-distance mobility,” says Friedrich Eichler, head of Volkswagen powertrain development.