Today German publication Bild reported that Audi were to pull out of DTM and the WEC to join F1. The route into the sport would be to buy Red Bull Racing and enter the sport with an Audi engine in 2018.

The bad news for Christian Horner was that Bild claims Stefano Domenicali is lined up as team Principal for the team.

However, Audi responded this evening claiming the Bild report was “pure speculation which requires no further comment.”

Audi’s parent, VW, are implicated in what may turn out to be the global auto industry’s biggest scandal ever.

TJ13 reported last week that the US Environmental Protection Agency (EPA) has discovered VW have been deliberately cheating on emissions tests. This is estimated to affect 500,000 diesel cars sold in the US.

However, diesel is a niche fuel in America, and accounts for just 1% of cars sold. In Europe that number is 50%.

VW have developed emission control systems which are fitted and working on their luxury cars, however on certain cheaper models, they have fitted the systems but coded the engine management software to switch off these systems when the car is not being tested.

The car’s computer can detect when the car is in a test environment from throttle, acceleration and other car control inputs. The emissions control systems are then switched on, but switched off when the car returns to the road.

This means less expensive materials can be used in the exhaust systems, and fluids used in the catalytic emissions converter are only used should a car be tested. This saves the user from having to replenish these fluids.

The fine in the USA is estimated to be $18bn for the 500,000 cars affected. However, one auto industry expert suggested the number of VW cars affected in Europe could easily number 30 million. Fines due on this scale of “illegal” cars could cripple even a company of the financial might of VW.

Millions of customers have invested in cars that have fuel emissions that attract either a subsidy or reduction on car tax. These cars may now be re-rated.

The company performing the testing in the US says emissions exceed the claims by a factor of 10-30 times.

Martin Winterkorn who recently assumed control of the VW boardroom stated: “I personally am deeply sorry that we have broken the trust of our customers and the public.”

VW’s share price fell 18% yesterday and further falls are expected today as the scale of the crisis becomes fully understood. Germany’s stock market index, the DAX also fell 17%.

The German government has ordered an “extensive examination” of diesel cars and VW executives face criminal prosecutions.

The “cheat” software was fitted to the less expensive end of their car range, as the impact of the system fully operational on a permanent basis would have affected the price VW could offer the car to consumers.

The biggest previous recall of cars was performed by Toyota, following the malfunctioning equipment that caused the cars to accelerate without user input. This recall was for 9 million cars.