Catalytic converter woes

Have 1999 Lexus ES300. My VSC, Check engine, Air bag lights are on all the time. Mechanic has changed oxygen sensors and cleaned out some other gizmo in two attempts. He says it’s my catalytic converter. However, he said if I do replace it something has caused it to go bad. What is anybody’s guess? How long do I have before bad things happen to my engine?

You need to find a better mechanic. This one is just throwing parts at the problem(s) and wasting your time and money.

Agree with the other poster - find a different mechanic. There is something common going on here that is causing these lights to be on (fuse, wire, computer). Lets think about this, would the CAT cause your air bag to go off… I think not…

Thank you so much.

Thank you for the help. The air bags did not go off the little red light on the dash keeps blinking.

Are you talking about two separate problems, or, are you saying that one caused the other? I’m doubtful of that.
What does VSC mean? It could mean Vehicle Speed Control; but, does it?

VSC is the automatic vehical skid control which controls which wheels brake and which do not.
I contacted the service manager of Lexus in Eugene, Oregon and he said to tighten my gas cap, that could be letting air in and confusing my computer. I tried that and after a few miles of driving the lights have gone out. I don’t know if that will continue, but I have my fingers crossed.
I really appreciate you reply. In case they don’t stay off…any suggestions are gladly accepted.