8 mai 19

Amended Euro 6d: EVAP and ISC could cause more homologation delays

Just when you think things cannot become more complicated, Europe makes life even harder for OEMs with an amendment to the Euro 6d-Temp emission standard. Tougher conditions for evaporative emissions testing (EVAP) and emissions measuring of cars while they are in service (ISC) may jeopardise the availability of some models.

2018 has been a difficult year for carmakers in Europe. The introduction of a new type approval method called WLTP caused serious bottlenecks and therefore the unavailability of many models for months in a row.

OEMs have barely had time to recover from the WLTP storm and yet another cold front is moving in. Emissions of newly type-approved passenger car models must now be verified by the OEMs during five years or 100,000km after their first registration - something that is indicated by the ISC suffix (for In Service Conformity). To add to the complexity, Europe has also adjusted the evaluation procedure for evaporative emissions (EVAP). This could yet again cause bottlenecks in the type approval procedure.

The next step: In-Service Conformity Test (ISC)

Cars that pass the RDE test comply with either the Euro 6d-Temp or the Euro 6d emission standard, depending on the NOx emissions measured. For the 6d-Temp standard, the RDE Conformity Factor (CF) for nitrogen oxide emissions is 2.1. The RDE conformity factor for Euro 6d amounts to 1.43 and is mandatory as of January 1st 2021.

So far, there’s nothing new. New models launched by car manufacturers generally comply with Euro 6d-Temp. Just a handful of cars (from Alfa Romeo, Jaguar and Mercedes) do better than what is legally necessary today and already carry a Euro 6d approval. That makes them the most ‘futureproof’ of all.

With the introduction of the new ISC, the evaluation procedure must now include emission tests on vehicles that are in circulation during five years or 100,000 km after their registration. These tests are mandatory for newly type-approved passenger car models from 1 January 2019 and from 1 September 2019 for all newly registered vehicles.

EVAP: evaporating petrol

And then there’s the EVAP amendment. Petrol-powered vehicles have a pressure equalization system in their fuel tank, which prevents negative pressure from forming. Inflowing air avoids the contraction of the tank while driving. When the fuel is heated, the pressure equalisation line prevents the tank from bursting. The petrol vapours are collected and temporarily stored when the vehicle is stationary. During driving, the fuel is supplied to the combustion, thereby minimising waste. Some of it evaporates, though.

The EVAP emissions test considers hydrocarbon emissions (HC) that occur during driving and parking. To pass the new test, which is mandatory from September 1st 2019 for new type approvals, a car mustn’t emit more than 2g of HC within a period of 48 hours. Diesel engines do not need to run the EVAP test procedure as diesel is not volatile, but the approval remains the same.

Impact on fleet: delays

So, when you see Euro 6d-Temp-ISC, Euro 6d-Temp-EVAP, Euro 6d-Temp-EVAP-ISC on the COC of a car, you know what they stand for. The suffixes EVAP or ISC do not offer any added ‘protection’ against banning from low-emission zones or extra taxation. To be on the safe side, Euro 6d vehicles are recommended over Euro 6d-temp cars – and especially over Euro 6c cars, which have not been road-tested (RDE) and could face headwind in the near future.

The real impact on fleet comes from the new EVAP procedure, which may again cause bottlenecks and thereby increase lead times and limit availability. There is however no reason to believe that the effect will be as disastrous as WLTP and RDE, but some OEMs seem less confident than others.

Volkswagen Group's sales chief Christian Dahlheim told Autonews.com that to pass the latest tests nearly all engine-transmission variations will again have to go through "time consuming" WLTP certification processes. "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," he said.

The new regulations were only published in their final form at the end of November 2018 and, in the case of new vehicle types, required compliance already at the start of 2019. "It remains challenging because the effort for everyone involved with the new processes has risen enormously,” Daimler’s sales chief Britta Seeger told Automobilwoche. "In 2018, we learned a great deal. We can now plan better," she said.


Source: VW AG


Picture copyright: ADAC, 2019




Authored by: Dieter Quartier