I just went through the hassle of replacing the catalytic converter on my 1997 Toyota Camry for the second time.  First off, from what I’ve read, these things aren’t supposed to die in the first place.  They end up being killed if something else is wrong further up the chain of events in the whole “burn fuel, move car” business.  (As you can tell, I’m not much of a car guy.)

If unburnt fuel is sent to the exhaust system, it gets burned off in the catalytic converter so it’s not sent out your tailpipe.  (I guess that’s bad for the environment.)  When an excess of fuel is being burnt off in the catalytic converter, the temperature starts to rise inside there.  If it gets into the range of 1400 – 2300º F, you’re at the point where the precious metals and other things inside the catalytic converter start to deteriorate, according to the manufacturer of my aftermarket part.

Other things can make these things go bad, too.  Oil or other things leaking into the exhaust system that shouldn’t be there can cause problems, too.  I’m not exactly sure about all the stuff that can happen, but I know that when your check engine light comes on, you’re facing a potentially costly repair and the more you know about the issue and your rights, the better off you’ll be.

So here’re the important things I learned through the process of replacing the catalytic converter twice in my car:

  • Make sure you have your mechanic determine what caused the failure in the converter in the first place.  Get whatever it is fixed so it doesn’t happen again later.
  • New aftermarket catalytic converters are required by federal regulations to carry a 25,000 mile warranty.  Don’t let your mechanic tell you that you have to pay for another catalytic converter within that warranty period.  Make sure your mechanic gives you the warranty information card supplied by the manufacturer of the converter. (See this PDF from the EPA for an outline of all your mechanic’s legal obligations.)
  • The original catalytic converter in your car is warrantied for at least 8 years or 80,000 miles.  You shouldn’t have to pay anything to get it replaced with an original part by the car dealer.

That pretty much sums it up.  I was looking at having to spend another $500 on a repair I had done only 13 months ago.  I’m glad I took the extra time to search online for details regarding my part’s warranty.