What Was Dieselgate? And Should I Pay Attention to Diesel Scandals?

Everyone loves a good bit of intrigue, especially one that involves car technology and one of the motor industry’s biggest players. Yep, that's right. I'm talking about Dieselgate, one of the biggest ever scandals, that first broke in 2015.

So, sit back and get some popcorn at the ready. I’ve written an account of everything you need to know about the diesel scandal and the sneaky car engine technology that caused it.

What is the diesel scandal?

The diesel scandal (also known as Dieselgate or the Volkswagen Emission scandal) all started with one German car manufacturer – Volkswagen. (You might have guessed that from the name!)

On 18th September 2015, the Environmental Protection Agency (EPA) served the company with notice that they had violated the Clean Air Act. It had found compelling evidence that Volkswagen has programmed its turbocharged direct injection (TDI) engines to alter the findings from emissions tests.  

So, the TL;DR (too-long-didn’t-read) version is that Volkswagen was caught using illegal software – dubbed the ‘defeat device’ — to trick emissions testers into thinking that the nitrogen oxide given off by the engine was less than it actually was.

As well as affecting the 42,000 VW-manufactured cars in the US, the company also admitted that the defeat device was fitted to around 11 million of its cars across the world, including around 8 million in Europe.

The company pleaded guilty to the charges in January 2017 and was fined $4.3 million by the US. The former CEO of the company, Martin Winterkorn, who resigned in 2015, was charged with conspiracy and wire fraud.

Following the discovery that Volkswagen had been caught cheating on emissions, it was also found that several other leading car companies had been in on the action too. Some Chrysler, Nissan, Renault and Mercedes vehicles were all found to feature some form of defeat device.

The scandal lead to the recall of millions of vehicles across the world, severely damaged public trust in car manufacturers and altered the environmental esteem that we once held diesel cars in.

The ‘Defeat’ device

Dubbed the ‘defeat’ device, investigators found that Volkswagens’ diesel engines had a special piece of computer software that could detect when emissions were being tested under laboratory conditions and falsify readings so that they were lower than they actually were in reality.

How the software worked specifically still hasn’t been made public. But the device was so sensitive it could work out when the emissions of the car were being tested by monitoring subtle aspects of the engines performance – all of which change when the engine is put into a testing mode in a controlled situation in a lab.

The amount of actual nitrogen oxide emissions released by the cars is around 40% more than thought – a significant figure.

Why does the diesel scandal matter?

It matters because one of the world’s biggest car manufacturers was found to purposely falsifying emissions data in its car. That’s a biggie.

And what’s more, it wasn’t an accident. Volkswagen had designed and fitted a device to 11 million of its cars. So it’s unlikely it was just the work of one lone, emissions-loving worker either. It was the design of bigwigs at the top of the company.

It could mean that all of what we’ve previously considered about diesel-powered cars being better for the environment is incorrect.

In effect, governments across the world have wasted billions promoting diesel cars as environmentally friendly when they were actually the exact opposite.