Maybe not exactly the same, but the B mode on hybrid cars sound similar. When you are driving down a large hill (e.g. on a mountain) eventually the battery wil

Maybe not exactly the same, but the B mode on hybrid cars sound similar. When you are driving down a large hill (e.g. on a mountain) eventually the battery will become fully charged, so you can't use regenerative braking anymore. To provide some resistance so you aren't effectively driving in neutral, the car will spin the engine at high RPM without supplying any fuel (I'm not sure how this works in terms of lubrication, as I understand the fuel provides this too?). You can also engage B mode which does this at an earlier stage, so have more control without having to use the brake when driving down steep hills (like engaging a lower gear). London hybrid busses do the same thing, as they come to a stop you can hear the engine spinning at high RPMs.