SR20DET boost but no power

[Edyz7s]

Okay, yes their are threads about this but they all seem to point out to boost leak.
Here the thing with mine. So today I installed a new o2 sensor and knock sensor. The reason for installing o2 sensor is because I have bad gas mileage and hope this would make it better.
And for knock, I never replaced it since I got the motor and when I took out the old one, it was still original.
Inspecting the old knock sensor I found 2 cracks, one small and the other slight bigger. I heard these do go out and usually don't work well if its cracked.

So, starting up the car it started up fine. The only thing i noticed was it was idling a bit higher from a cold start. Usually it goes away when the motor gets hot, but it took awhile this time.

I take it out for a test drive and noticed it was horrible on WOT. Pushing half the throttle i felt it was trying to go but it just did not. I didnt remove as much to install these 2 but everything is in place. I didnt get to torque to spec the knock sensor but I seriously dont know what happened to all my power and clueless whats the cause after these new installations.