Clogged catalytic converter?
 

Could any one tell me what the symptoms of a clogged cat. could be? Upon accelerating at high rpms my car makes a horrible whistle. At first I thought it was a leak in the inlet hose to the turbo. But I monitored this and realized that could'nt be, because if Im at lower rpms, but still at max psi, there is no whistle, but at high rpms it whistles.(also I checked thoughrouly and could not find any leaks.) im not sure if Im correct on that, so please correct me if Im wrong or tell me anything anyone knows. Thanks!

With a bad cat you will usually experience the car shuddering or sputtering at higher engine speeds and loads, and you may hear a rattling noise coming from the cat itself.

A clogged cat will run much hotter as well, jack up the car and pull the cat out, see if you can see through it. If you take it out go get yourself some stainless hardware to put back in there.

Good luck.

The car does run very, uneven I guess you could call it. When flooring it, the car does seem to accelerate unevenly. It just kind of feels like the car is clogged, if that makes sense. Also is it at all possible the clogged cat could set off the knock sensor?

i think mines clogged also. I pulled the huge ghetto 5in. muffler off and the car is still quiet as hell. anyone else remove their muffler. wonderin how loud it was.