The new Chief Executive Officer of Volkswagen Matthias Müller, former head of Porsche, has assured investors and customers of thorough probe into the emission cheating scandal, which is creating tremors for the German's leading automaker.

Soon after assuming the new responsibility, Müller spoke for the first time addressing the company's customers and investors in his letter. He has also promised that such misconduct will never happen again. He also held discussions with representatives of labors. 

Martin Winterkorn, the predecessor of Müller, was forced to resign last week over the scandal.  Following the surfacing of rigging of emission results in Volkswagen diesel cars, the German auto major is facing turbulent situation that's damaging not only company's brand value built up over 78 years, but also German's image.

"We'll be relentless in getting to the bottom of this-- fast, open and as decisively as possible," said Müller, who took charge as CEO on last Friday. The new chief of Volkswagen Osterloh has also decided to work closely with labor to maintain high quality standards and regulatory norms at the factory level. 

According to news making rounds in the media, an engineer at Volkswagen earlier in 2011 alerted the company about the cheating over emission tests. The warning came into light after the probe began on the emission tests cheating, according to a German news paper. However, Volkswagen didn't respond to provide details on it saying it wouldn't comment on news paper speculation.

It's learnt that Bosch had also warned Volkswagen in 2007 over the usage of its software. Bosch says its software was for only company tests, but not for normal driving conditions. The devices are being used to examine the engine during the vehicle test to find out the defects in the engine. This is being done for enhancing the car's performance and to better in test results.

The latest emissions scandal has landed Volkswagen in a serious problem as it leads to legal and environmental issues for the German automaker. It's estimated that about 11million diesel vehicles, equipped with software that cheats emission results, were sold across the world.

The Environmental Protection Agency has found that Volkswagen has installed cheating software in Passat, Jetta, Golf and Beetle models. The software rigs the results in emission tests for these diesel vehicle models. 

The Environmental Protection Agency has also revealed that the cheating software facilitated these models to belch up to 40 times over the mandate of permissible harmful fumes. This enabled to increase the driving performance at the cost of more emissions in normal road conditions. But the software only shows the emission results is only at the lower end.