Hey There.
I had the same issue with my Cultus EFI 2012. I changed all throttle sensors, butterfly etc but problem still remained the same. Then I noticed that when the RPM are high (with clutch pressed or idle) it seems that the Accelerator is stuck, I pulled my accelerator back with my foot and RPM went down.
If this test goes same with your car then change the Accelerator cable. It is damaged and causes the hurdle for throttle / butterfly to go back to normal.
