Loss of power

Good I have a Mitsubishi CharioT Grandis Motor Gdi 2.4 and when he warms he works half lazy as if he drown or lacks fuel in all speeds, then I let go of the accelerator for a while and I step on it again recovers to some extent or I have to lower the march since he has a sequential box but only to some extent. Can someone help me, it should be noted that the silencer has perforations will that be the deceased?

It is not the problem of the silencer with perforations, it could be the problem of obstructed catalytic but not of the broken silencer, but if the lack of power appears in hot could be a problem of fuel injection, is that model bencinero or petroleum?

I have always loaded 95 octane gasoline although I have noticed that it comes out a lot of water for the escape, it will be that quality is very bad?