Bad cat?

[jiangtao]

Just curious as to what the signs of a bad catalytic converter are? I have noticed that my car sometimes is very quiet and sometimes very loud when listening inside the car. I don't have a sulfur smell or anything like that,but it does feel restricted sometimes. I have an '86 with 98k on the clock and I'm sure it's about time to have them looked at! My car is always running rich also.

 

[jimmers]

When mine went bad you could hear the small parts rattling at idle and when driving. You might even notice a power loss if they are clogged.

 

[jsinga]

A clogged cat will show up if you run the car at about 2000rpm for 30sec or so. See the exhaust manifolds start to glow a dull red? Sure sign of a clogged cat. The rattle on mine was a pre-cat comming apart. Eventually it broke up and REALLY plugged up the main cat. It would barely make enough power to get in high gear.
If you think it's rich with and the computer doesn't adjust it change the oxygen sensor if it's old. It's kind of a pain to get to and you need the special socket. But the one wire sensors aren't $20 for the last one I bought. I think AutoZone will loan the socket.
Try a few bottles of good fuel system cleaner, old injectors can leak. If someone can look at it with a scanner you can find out if the computer is trying to cut back the fuel.

JS

 

[Vettefan87]

I have always just used an open ended wrench with a rubber mallet. It seems to work for me.