Can't rev to redline

[Jetblack]

My car seems to struggle when trying to rev past 5k rpm. at idle or while driving. t25 turbo. just doesn't seem right. any clues of what to check

 

[Defiant]

1.) Don't think of doing this to an unloaded engine.

2.) How long since a tune up? How old are the plugs and wires?

 

[Jetblack]

It's been like that ever since I bought it back in March and all of that has been changed to no avail