So just recently the whole exhaust tone of my car has changed and I'm having boost level issues. My car is alot louder and sounds like i'm running a straight pipe, but then sometimes at the higher RPM's my exhaust almost sounds like it is a bit plugged up and boost levels dont go much higher than 10psi. The issues at high RPM are really inconsistent. The car is always loud at idle though.

My buddy thinks my HFC is partly blown out. This was happening to one of his cars a long time ago and when he removed the CAT parts of it fell out.

What do you guys think?

We are have super bad weather right now or else I would have already removed it.

 

Anyone?

 

Tap on the cat with rubber mallet if you hear stuff rattling around its most likely blown.

 

Are these normal signs of a CAT being blown, or is this most likely something else?

 

Tap on it like he said and if it rattles it is bad. you could also just remove it and check. 4 bolts..not to hard.

 

I cant get under my car right now. The weather is a constant storm right now.

I've removed my CAT several times before.

 

Sounds like a blown cat to me. Mine got so bad I needed to replace the full exhaust because I had that honeycomb crap stuck in all of it.

 

Did you experience low boost levels as well?

 

Can u just leave the cat out? How does an evo react to having the from
the cat back removed?

 

i had a 2g gsx an i had a blown cat an was loosing boost and as soon as i got a new one i was boosting like normal but i havent had a problem with my VIII yet