EC Offers Enforcement Guidelines for Emission Cheaters

The European Commission has issued guidelines to coax European Union member states into doing a better job of detecting and sanctioning illegal “defeat devices” designed to evade emission rules.

Defeat devices have been banned since 1998, but member countries rather than the EC are responsible for enforcement. The guidance reflects the EC’s frustration at the reluctance of some countries to investigate possible wrongdoing—akin to the cheater software Volkswagen AG secretly installed in 11 million diesel-powered vehicles—and impose penalties if they find it.

Some EU members have complained that allowable exceptions, which allow engines to exceed emission limits temporarily for the sake of durability, aren’t clearly defined. But the ECU pointedly notes that no country complained about a lack of clarity until after U.S. regulators uncovered VW’s cheating in September 2015.

The EC says carmakers should be required to justify the need for an exemption by showing there is no technical alternative already on the market, proving the intended exemption will hold emissions to the lowest possible level and documenting the engine damage that would result by not applying an exemption.

The guidelines also suggest regulators pay especially close attention to emission strategies that produce higher emissions when a hot engine is restarted, result in higher emissions outside a specific ambient temperature range and use controls that are indexed to timers or vehicle speed.