its your cam timing it might be off a tooth check your timing belt if your missing a tooth on the belt it could have skipped during high revs get a new belt and zero out your cams by the hole on top of the cam plates that coves the cams line up the holes on the plate and the cam with a drill bit and you at zero but make sure yout bottom end is at tdc do that and it will fix your problem

 

but how come it doesnt so this when the car is warmed up.

 

if might be your idle control screw or your oil pressure could be low

 

any codes??