I’m sure VW would agree as they hate being the only maker caught out playing little games with emissions testing.

But are they all alone?

According to this a test performed for a German environment association allegedly proves that an Opel Zafira 1.6 diesel shows higher emissions when tested with all four wheels turning rather than two as per usual on a rolling road. GM (Opel is a GM brand) deny everything.

Have a smoking Zafira. You’re welcome.