Volkswagen has presented its solutions to diesel engines affected by the CO2 emissions scandal to the Federal Motor Transport Authority in Germany ahead of a planned recall in January.

The manufacturer announced that the measures involve “minor hardware” changes in the case of the 1.6 litre TDI engines and a software update in the case of the two litre engines.

A statement issued by Volkswagen said: “The final technical solution for the 1.2-litre diesel engine will be presented to the Federal Motor Transport Authority at the end of the month and is expected to comprise a software update.”

The statement said that the corrective measures had been ratified by the Federal Motor Transport Authority, adding that “there is now clarity regarding the correction of the irregularities for the majority of vehicles affected.”

A “flow transformer” will be fitted directly in front of the air mass sensor on the 1.6-litre EA 189 engine. This is a mesh that calms the swirled air flow in front of the air mass sensor and will thus decisively improve the measuring accuracy of the air mass sensor.

The air mass sensor determines the current air mass throughput, which is a very important parameter for the engine management for an optimum combustion process.

A software update will also be performed on this engine.

The time needed for the implementation of the technical measures is expected to be less than one hour.

The two litre engines, meanwhile, will get a software update which will take around half an hour to implement.

Volkswagen’s statement added: “The objective for the development of the technical measures is still to achieve the applicable emission targets in each case without any adverse effects on the engine output, fuel consumption and performance. However, as all model variants first have to be measured, the achievement of these targets cannot yet be finally confirmed.”

Based on the approach of the Volkswagen brand, the Group's other brands – Audi, Seat, Skoda and Volkswagen Commercial Vehicles – are also planning corresponding measures for their affected vehicles.

In connection with its efforts to carry out a full recall of effected vehicles Volkswagen AG is forgoing the right to plea on the grounds of statutes of limitations in respect of any warranty or guarantee claims due to the software installed in vehicles with EA 189 engines until December 31, 2016, as long as the rights to make any such claims have not already expired.