Volvo 850 power loss under hard acceleration

[Jaumme]

My 1993 Volvo 850 t5 is losing some power in hard acceleration when you go full throttle the car pulls normally for about 2 seconds then hesitates a lose the power it keeps pulling but like half the power. I checked the vacum lanes from the turbo thenintercoler piping and its ok the tcv works properly but I unplugged it and thest drive the car and just did the same thing. The car has 63k kilometes. No codes and no engine light the car runs of except for that, if u accelerate gently the car keeps going but if u go hard on throttle it does that, what shsoid I look for?