- TDI of the Jetta is one of the lowest emissions diesels in the world
- 41 mpg highway and emissions reduced by 90 percent
- Jetta with Clean Diesel is available as sedan and SportWagen
The Jetta is a prime example of the art of German engineering. No other car developed in Europe can claim similar success in America. In parallel to its gasoline versions, since August 2008 a 103 kW / 140 PS strong Clean Diesel has been offered on the Jetta in all 50 states of the USA – it is one of the most fuel efficient and cleanest engines being marketed across America. This successful model is available as a sedan or wagon; the latter is called the “SportWagen”.
The Jetta’s new four-cylinder turbo-diesel is so fuel efficient (30 mpg city / 41 mpg highway / manual transmission) and so clean, that the Jetta TDI and Jetta SportWagen TDI are eligible for a 1,300 dollar tax credit in the United States. The fact is that from the very first day they are driven, cars like these Volkswagens make a contribution toward drastically reducing noxious emissions and the costs of car driving. Because compared to a similarly powered gasoline engine, fuel economy on the Jetta TDI and Jetta SportWagen TDI is up to 35 percent better! That helps the environment. Immediately.
A key aspect of the technical design on the Clean Diesel is its ability to reduce nitrogen oxides. In the case of the four-cylinder common rail TDI, the engineers from Wolfsburg achieved this goal by means of internal engine modifications and – instead of a SCR catalytic converter as on the Touareg – they used a NOx storage catalytic converter. This piece of technology is not as complex as the SCR catalytic converter, but due to the lower weight of the Jetta it leads to the same desired effect: up to 90 percent lower nitrogen oxide (NOx) emissions and impressive fulfillment of the BIN5 emissions standard. Details of this Clean Diesel technology:
Exhaust gas recirculation reduces nitrogen oxides
Diesels are more economical than ever before. But they create a problem that needs to be addressed: although high combustion chamber temperatures promote fuel economy – at the same time they also favor the generation of nitrogen oxides (NOx).
Within certain limits, this problem can be resolved by optimized combustion chamber geometries and extremely precise injection processes at extremely high pressures, as Volkswagen has proven. However, in dealing with emissions it is also necessary to limit combustion temperatures and reduce the concentration of oxygen with which the nitrogen reacts to produce nitrogen oxides. Both goals can be accomplished by external exhaust gas recirculation in the combustion chamber. The gas is taken from the exhaust system and is cooled on the way to the combustion chamber. These actions can reduce temperature-dependent nitrogen oxide emissions by up to 60 percent in the ideal case.
NOx storage catalytic converter eliminates rest of the nitrogen oxides
The rest is treated by the NOx storage catalytic converter. It soaks up the nitrogen oxides like a sponge with very high efficiency. Similar to the particulate filter, it is cleaned regularly and without the driver noticing. Engine management switches over to an operating mode with richer combustion for a few seconds to accomplish this.
The NOx storage catalytic converter is intended for use with diesel fuel that is extremely low in sulfur (sulfur content less than 15 parts per million = ppm); otherwise it would lose its efficiency due to sulfate formation. In the USA, large scale introduction of this diesel began in October 2006.
This much is certain: The Jetta TDI is extremely economical yet very agile. It accelerates to 60 mph in just 8.5 seconds and attains a top speed of 127 mph (204 km/h). This contrasts with a very favorable highway fuel economy of 41 mpg. And the word is out. Dr. (Engineering) Jens Hadler, Director of Volkswagen Engine Development had this to say: “High fuel prices and a significantly altered environmental awareness has led more and more US car drivers to favor diesel every day. Therefore, many car drivers – especially in California – have been looking forward to a super clean diesel like our TDI. I think this engine will help the diesel make a breakthrough in America, because it consumes extremely little fuel and at the same time can cover enormous distances on one full tank. And in a country as large as the USA, that is an immeasurable advantage.” Yet it is a characteristic that fits in perfectly with America: 320 Newton-meters of torque at a low 1,750 rpm. This transforms the Jetta into a genuine cruiser when necessary.
Note:
All data and equipment contained in this press release apply to models offered in the USA. They may differ in other countries. All information is subject to change or correction.
TDI, TSI, DSG and Twincharger are registered trademarks of Volkswagen AG or other companies of the Volkswagen Group in Germany and other countries.
Looking for more? Have a look below.
- Fuel Cells to Clean Diesel, Volkswagen Presents Array of Innovative and Economical Powerplants at Los Angeles Auto Show
- 1139 km on just one tank in a Jetta TDI Clean Diesel
- Volkswagen Jetta TDI in Fuel Economy Guide 2009
- Jetta TDI Cup: Drivers Secure Grid Positions in First All Clean-Diesel Race
- Volkswagen, Clean Diesel & at SEMA
