Engine never rev down to idle (Vehicle Movement Component)

Hello, did anyone ever tried to put the Sport car (or any other ready made car in BP) of unreal engine in manual gear mode, disable the auto reverse and just rev the engine while monitoring the RPM?

The engine never rev down after releasing the accelerator…I check the value of the input throttle and it’s 0, but the engine doesn’t rev down to idle regardless of frictions and rev down setup in the vehicle movement component.

I tried with the city sample vehicle package as well and same result. Why isn’t the engine naturally fall back to it’s idle RPM without having to tweak anything?

Posted a bug report about it and it got deleted so not considered a bug, although it is still not fixed…