Petrol and diesel engines

Investing in a cleaner future for conventional engines

At the same time as we develop exciting new alternative fuels and powertrains, we invest in making our conventional petrol and diesel engines cleaner and more efficient.

The role of the conventional engine

The internal combustion engine continues to be the most popular means of powering vehicles and it will continue to play a role for the next 20 to 30 years. In our Environmental Challenge 2050, we target a 90% reduction in our 2010 vehicle CO2 emissions level, which will require significant improvements in conventional engine performance, as well as making next-generation low or zero-CO2 vehicles widely available.

We are investing methods and technologies to help us make the most of every drop of fuel and achieve the lowest emissions levels from our petrol and diesel engines. We are producing new engine designs to secure the best balance of performance with efficiency, helped by the great knowledge and experience we have gained in developing our hybrid power systems where we combine a very efficient petrol engine with an electric motor.

Making the most of every drop of fuel

The challenge with a petrol or diesel engine is to get the most energy out of every drop of fuel. If you use less fuel, you produce fewer emissions and help protect air quality. There are fundamental things you can do with an engine to achieve this. You can make the combustion process more efficient, so less fuel is wasted. You can also reduce the engine’s weight and cut the amount of energy lost through friction between its working parts. To make our engines lighter we have introduced new lightweight materials, including resins and plastics, and have combined individual components to single units that weigh less and take up less space. To reduce friction we have produced special coatings for internal components and developed new lubricants for smoother running.

The hybrid petrol engine in the 2016 Prius demonstrates just what we can achieve – it is the most thermally efficient petrol engine in the world, which means less energy is being lost as heat inside the engine and more is available to drive the wheels. Although this engine is part of a hybrid system, we are seeing similar gains being made in our new generation of conventional engines, including the 1.2 and 1.0-litre units we use in our Yaris and Aygo models.

We are achieving better control of the amount of fuel used with more precise fuel injection systems, intelligent valve timing and improved design of the engine combustion chamber. Our new generation petrol engines are also able to run on different operating cycles to suit different driving conditions – for example when you start up and when you are driving on the open road – applying know-how from our hybrid programme.

It isn’t just under the hood that fuel savings can be made. We combine our engine technology with aerodynamic designs that help our cars move smoothly through the air, reducing the drag effect and bringing down fuel consumption.

Advances with turbo technology

Using a turbocharger allows more power to be produced from a smaller capacity engine with lower fuel consumption and, consequently lower CO2 exhaust emissions. Achieving this balance requires careful engineering and we have succeeded in applying the technology to a new range of highly efficient petrol engines. These smaller engines weigh less than their larger, naturally aspirated equivalents, which also has a positive impact on efficiency.

We have also developed more efficient direct-injection turbodiesel technology to produce a new family of diesel engines that achieve exceptional thermal efficiency together with higher levels of torque and fuel economy. Our new advanced diesel combustion and aftertreatment system also strongly reduces NOx emissions, helping protect air quality.

More about

What is Hybrid? What is Hybrid? Discover how our Hybrids have been designed to make your life easier. Simple Truths Simple Truths Discover the simple truths behind eight common Hybrid misconceptions. Toyota FAQs FAQs Here you can find some popular frequently asked questions and answers to help you with your decision to switch to hybrid. Toyota FAQs FAQs Here you can find some popular frequently asked questions and answers to help you with your decision to switch to hybrid.