WLTP emissions loophole closed by EU lawmakers

The European Commission has tightened the WLTP test regime for new cars sold in the bloc after claims that automakers were gaming the tests.

The updated regulation, which came into force in February, requires automakers to switch on all emissions-saving technology, such as the stop-start function, and use the same driver-selectable modes for each model tested, for example Eco mode instead of Sport mode.

The Commission discovered that automakers were turning on functions during tests that increased emissions in the runup to the introduction of WLTP testing on Sept. 1, the green pressure group Transport and Environment said.

The Commission found that some automakers were manipulating tests to burn more fuel and increase emissions with methods such as switching off the start-stop function in cars being tested, adjusting the gear-shift patterns, using the Sport instead of Eco mode, T&E said.

By artificially increasing their CO2 emissions now, automakers hoped to weaken future reduction targets, T&E said.

The manipulation partly explains why there is a huge disparity in average emissions between different automakers, T&E said.

CO2 emissions increased when homologation tests in Europe switched to WLTP from the former NEDC homologation regime. The range of the increases was between 1 percent to 81 percent depending on the automaker, T&E said. It did not name the brands.

ACEA, the body representing automakers selling cars in Europe, welcomed the rule tightening.

The changes make the WLTP testing procedure "even more robust and to prevent any test manipulation," ACEA said in a statement.

T&E warned that automakers might have to retest models.

"If carmakers want to sell them in 2020 when WLTP values for 2025 CO2 targets are measured, they either have to prove to their approval authority that they meet the new requirements, or re-homologate," Julia Poliscanova, clean vehicles and emobility manager at T&E, told Automotive News Europe.

"It remains to be seen whether or not the new WLTP amendments will have closed all the loopholes. It is something we will be watching closely in the course of this year," Poliscanova said.

T&E called for governments across Europe to stop using CO2 to calculate tax bands for cars tested before February this year. "The data suggests the WLTP figures are unstable," it said.

Automakers are under increased pressure to find loopholes in the testing system as the EU introduces tougher CO2 reduction targets to cut greenhouse gas emissions.

The EU replaced NEDC with stricter WLTP tests to reflect better the on-road fuel economy and CO2 emissions of new cars.

Under NEDC the gap between emissions figures from laboratory tests and those achieved in independent real-world tests increased to 31 percent in 2013 from 8 percent in 2001.