Ok so here's how it all started.
I was running about 23 24 degrees timing, no knock everything's handy dandy my cars pretty fast.
One day I slammed my rev limiter in 1st gear and the car didn't like that and choked out leaving me sitting on the highway. So. After a few attempted cranks, it finally chokes up and comes to life, throws 2 codes, clear them, never see them again.
I notice that whenever my car gets into boost it makes a hissing noise.
Thought this to be a problem with the injector orings leaking air from the advice of someone. Cool we'll do them, did them today and the car drove fine for a bit. No leaks of fuel and such of course. came home on lunch and drove the car back up. felt sluggish and crappy, still making this hissing noise, wasn't watching boost.
Came home finally and I figured lets do a pull and see what happens.
I do this and I see the interceptor hit 15 and up to 16 where it usually stops.
Well it kept climbing, I saw 20lbs on the display and immediatley got off. The car is slow as dog **** and overboosting. My exhaust is also very soft it seems like compared to what it used to be, not anywhere close to as loud as it used to be.
Anyone know what the problem could be?
My hit is on the Cat but would that cause overboost and the loss of power so suddenly like that?
Didn't see any smoke coming out the exhaust either.

 

The cat has to be plugged , thats exactly what they sound like.

 

Alright cool thanks I'm going to call them to come tow it monday and get er done.