Evo 4 Top end power loss

[immortalbrute99]

Hey guys! I own a 1996 evo 4 gsr, bone stock. Recently i have been having issues with my top end power. Its fine until about 5500rpms, where i lose a ton of power and it barely revs past it! Does anyone have any suggestions of what to look at to solve this problem?

 

[Andy6]

Have you got any diagnostic equipment? or any dash warning lights? And does it do the same thing under different loads. I.E stationary in neutral, accellerating hard etc etc?