After the chaos of last autumn’s new engine emissions tests, car makers are preparing and bracing for even tougher legislation covering stationary vehicles, and which could be more favourable to diesel models.
Volkswagen Group’s sales chief Christian Dahlheim said that to pass the latest tests nearly all engine-transmission variations will again have to go through “time consuming” WLTP certification processes, he’s reported by Autonews Europe.
“Compared with 2018, we are confident that we can dampen the effects of the second stage considerably. Nevertheless, we cannot rule out temporary limitations to some of the models in our range in the second half of this year.”
Daimler said the industry had little time to prepare for the second set of tests. The new regulations were only published in their final form at the end of November and, in the case of new vehicle types, required compliance already at the start of the year, the company said in a statement.
The forthcoming test will examine evaporation emissions from standing vehicles with switched-off engines in climate chambers.
The test designed to limit the number of volatile organic compounds in the form of gasoline fumes that can escape from the vehicle over a 48-hour period. When a vehicle is parked, rising ambient temperature and even solar radiation may lead the lightest fractions of gasoline fuel to seep out.
Vehicles have a carbon canister system designed to trap the vapours, but they have a limited absorbing capacity. This however is not really an issue for cars with compression ignition engines due to the very low vapour pressure of diesel fuel.
Separately, all new vehicles will also be subject to measurements of nitrous oxide exhaust during real-life, on-road operation (RDE-NOx). Diesels will not be allowed to emit more than 2.1 times the laboratory limit, or 168 milligrams per kilometer. The test goes into force 1 Sept..