The WLTP emissions and fuel consumption cycle comes into force today and promises to be more realistic

From today, the new test procedure for light vehicles harmonised on a global scale (WLTP – Worldwide harmonised Light Vehicles Test Procedure) comes into force, replacing the New European Driving Cycle (NEDC) tests, which turned out to be far less realistic than expected, since they only subjected cars to laboratory testing rather than real-world use.

The WLTP adds to laboratory tests that are stricter than the previous ones a new test (RDE) carried out with portable measuring equipment on open roads and under real traffic conditions, subjecting the car to different driving conditions. This offers a much broader range of samples which, together with the laboratory results, will provide much more reliable and accurate measurements of both the fuel consumption and the emissions that new cars entering the market actually produce.

The WLTP test cycle promises to deliver much more realistic data

The new WLTP procedure is more dynamic and performs a greater number of acceleration and braking tests than the NEDC, while also monitoring various factors previously not taken into account, such as the temperature at which the tests are carried out, the tyre pressure, and other tricks used by manufacturers up to now (Mitsubishi acknowledged at the time that to pass the earlier tests, it subjected the tyres to over-inflation during the fuel consumption tests).

Although the new WLTP cycle comes into force today, its implementation will be gradual, since the development of many models has been carried out with the aim of overcoming the requirements imposed by the NEDC tests. Thus, until 1 September 2018, the WLTC regulation will initially be applied voluntarily at the request of manufacturers (some of the new models, such as the Honda Civic i-DTEC 1.6, have already passed it), and within a year it will become mandatory for all new vehicles.

Pollution control is becoming increasingly serious. In light of the scandals involving diesel engines at the various brands involved, the EU authorities have tightened the requirements imposed on car manufacturers and have introduced new, much more demanding controls to be carried out under real driving conditions. These controls aim to monitor far more effectively how much cars pollute.

The new controls seek to determine the real emissions that a model produces under real driving and traffic conditions, and unlike the previous ones, they are not limited to mere laboratory tests based on theoretical data. If the new model that the brand intends to sell exceeds the permitted levels, it simply cannot be sold in Europe.

As with the previous tests, the new tests also include a laboratory trial, except that this has been improved upon compared with the previous one, and its conditions are much more demanding in terms of requirements and more accurate in results. In addition to these tests, vehicles must also undergo mandatory testing under real driving conditions.

Until now, when a manufacturer wanted to obtain type approval for its car regarding fuel consumption and emissions, it only had to pass the laboratory tests. This allowed some manufacturers to specially prepare their vehicles to pass those tests. Using special software, the vehicles detected when they were being subjected to one of those tests and automatically altered their operation so that, only during the test, they would reduce emissions of polluting gases and particulates expelled through their exhaust pipes.

This did not change how they operated on the road, where, free from control, the malicious software stopped working and the cars returned to their real pollution levels, which were above the limits set by the European Union.

Following dieselgate, the implementation of the WLTP test cycle has been accelerated

The need to impose new, stricter controls on emissions and fuel consumption has long been recognised. The diesel engine scandals uncovered in September 2015, stemming from the so-called “dieselgate” in the United States, did not prompt the change, but they did accelerate the activation and launch of the new tests.

The new and more demanding tests, the high fines yet to be imposed, and the multi-billion-euro costs that the brands that cheated must bear to compensate consumers for the damage caused will certainly, for some time, make car manufacturers think twice before attempting any form of deception or trickery to get past the controls. However, sooner or later it will happen again.

But as the saying goes, “Where there’s a law, there’s a loophole,” and since the ones who control the tests are the administrations of the countries themselves, rather than an independent body free from the economic interests that directly link the car sector to the economies of the countries that must approve its products, the risk of possible deception or fraud remains.