Could you be thinking of any of these?
* "Chatting gas" - This could be a slang term for talking nonsense or boasting, similar to "blowing smoke."
* "Chatting crap" - This is a more common slang phrase that means talking nonsense or saying things that are not true.
* "Chatting garbage" - This means the same as "chatting crap," but with a slightly more negative connotation.
If you provide more context, I might be able to give you a more accurate answer. For example, what was the conversation about? Who said it? Where did you hear it?