Catalytic Converter

I need to know something, how can you tell if you have a plugged cat converter? I think i have one that is plugged.. please help

If your converter is plugged then the engine will have a difficult time gaining revolutions and have a serious lack of power. Usually it will act like it wants to rev up but it will get to a point where the exhaust cannot get out of the engine and will choke it off. You will also see a lack of exhaust from the tailpipe.

Since your exhaust can't get out as fast as it needs to then there will be a corresponding drop in vacuum. (You can't suck air into a cylinder that has pressure still in it.) So you need to check it out with a vacuum gage. Often the vacuum will slowly drop off until the engine stalls (at idle). This is caused by pressure building up in the cylinders instead of going out the cat. So, low vacuum or slowly decreasing vacuum are signs of a clogged cat. I had a Ford Ranger once that the 'guts' blew out of the cat and clogged the muffler. I was in Kalifornia and had a hell of a time with the smog check. A good exhaust man at Meineke figured it out for me. Even the dealer hadn't been able to figure it out!