vapor(Vortices) effect problem?

[carraro0127]

 

 

when i updated DCS to latest version(Open Beta DCS 2.5.1.16978 Update 1)...then became it( Even though engine is cold on the ground then still exist)!what problem or known issue??have any workarround?!need help, thx!

Edited May 20, 2018 by carraro0127