The regulations, known as the Worldwide harmonized Light vehicles Test Procedure (WLTP), went into effect in the European Union this month. Under WLTP, plug-in hybrids are tested differently than under the previous regulations, known as the New European Driving Cycle or NEDC.
As a result, the effect of the fully charged battery has been reduced. That, in turn, has pushed the crucial CO2 emissions figure above 50 grams per kilometer. The cars lose tax benefits offered in many countries to ultralow-emissions vehicles.
In Germany, many plug-in hybrid models have fallen out of the category where they qualified for the 3,000-euro (about $3,500) subsidy, said Matthias Schmidt, an analyst for Sweden's AID automotive research company. In most cases, automakers will need to fit a bigger battery into the vehicle to keep the tax benefits, Schmidt said.
Automakers have to decide whether the extra cost to fit a bigger battery is worth the incentives given.
VW has stopped sales of the midsize Passat GTE, Europe's No. 2-selling plug-in hybrid. A VW spokesman said the model will not be sold again until next July, when an update for the Passat range is due. VW also stopped selling the compact Golf GTE, Europe's No. 4-selling plug-in hybrid, which like the Passat GTE will only return July next year.
The VW spokesman said its plug-in hybrid models were at the back of the line for WLTP testing behind more popular conventional gasoline and diesel models. "There is a bottleneck with the testing," he said. "We have to get priority for highest-volume models."
Porsche has pulled sales of its plug-in hybrid Panamera sedan and Cayenne SUV. "We will not start taking orders again until the cars are being built, the timing of which has not yet been confirmed," a spokesman said.
Plug-in hybrid versions accounted for 69 percent of Panamera sales in western Europe in the first half, AID figures show.
Mercedes currently has no plug-in hybrids available to order but will start selling them again within the next two months, starting with the S-class and E-class models. The C class is not due until next year, a spokesman said. All will record under 50g/km of CO2, he said.
Mitsubishi meets rules
Mitsubishi Europe, meanwhile, has overhauled its Outlander plug-in SUV, Europe's best-selling plug-in hybrid. The SUV has CO2 emissions of 46 g/km under WLTP, Mitsubishi said.