With the start of the 2021 calendar year, Audi has brought its entire range up to meet the new Euro 6d emission standards. A significant percentage of the models in the company’s current product range meet the stringent emission limit requirements of the Euro 6d-ISC-FCM emission standard.
From an organizational point of view, the transition of the entire wide range of products to the new standard is an extremely difficult task. The biggest challenge is to make the most of the test centers in Ingolstadt and Neckarlsulm – regardless of the coronavirus crisis and the associated restrictions on working hours and production processes. At the moment, a total of 193 models have been certified according to the requirements of the new standard, and most of them are included in the previous model range. Several more models will join them in the first months of the new year.
Great variety: The A4 and A5 model families include a total of 58 engine and transmission options
In this case, homologation authorities understand one model as one engine-transmission variant (MGV) in combination with the corresponding body type. In practice, this means a separate homologation for each transmission (engine/transmission combination) that is available for the respective model family, such as the 2.0 TDI with seven-speed S tronic and dual quattro. Accordingly, each body style — in this case a sedan, Sportback or Avant — is actually a separate MGV. Thus, for the A4 and A5 model families alone, the company must meet the requirements for a total of 58 engine and transmission options.
The Euro 6 emissions standard first came into effect for new car models back in 2015. Since then, a maximum of 80 milligrams of nitrogen oxides per kilometer has been in effect for passenger cars with a diesel engine, and 60 milligrams per kilometer for passenger cars with a gasoline engine. However, with each of the nine updates to this standard, the EU has each time tightened the rules regarding the methodology, cycles and processes within measurements, as well as the framework conditions for the tests themselves. The new Euro 6d-ISC-FCM standard, which comes into force on January 1, 2021, applies to all new car models and pays special attention to the so-called real driving emissions (RDE): in these RDE tests, which are carried out under certain road conditions, vehicles must also comply with the established restrictions. However, due to the greater possibility of measurement deviations on the part of the equipment, a tolerance of 0.43 was given to the results. In addition, Euro 6d requires an on-board fuel consumption monitoring system. Audi offers this technology as part of its engine management software.
Technologies: Twindosing on diesels and high volume particulate filter on petrol engines
In order to achieve below emission limits in all its models, Audi has made great efforts. The diesel engines use Twindosing technology, which is used in both in-line four-cylinder units and V6. Whether in the compact transverse engine models or the larger longitudinal six-cylinder models, Audi has been gradually introducing Twindosing technology as early as 2020 – for example in the Audi A3, A4, A5 and Q5.
For gasoline engine models, the focus is on particulate carbon, which is mainly emitted when the engine is cold. Since 2018, Audi has been equipping its vehicles with a petrol particulate filter. The filters in question have a particularly large volume and reduce particulate emissions to the atmosphere by up to 90 percent. You will find more detailed information, as well as various animations on how to clean exhaust gases in diesel and gasoline units, in Tech Focus.