Problems with usage in the MID

I have a problem, maybe it’s not a problem, but I’m not so sure. I noticed today with my omi that when I drive and let it roll out, which in the MID with usage starting from speed 80, the consumption slowly from 3.6l to speed 0 with usage 6,2l , rises without that I give gas. Is this the motor brake or how can I understand that? After 5s then again at speed 0 1,5l consumption is normal. Over 80km/H everything is OK, i.e. without gas give consumption 0.0l under 80km/H fän Is that supposed to be like that or what could be broken?? Greetings and thanks in advance Bluebyter