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Catalytic converter warranty

I think I’ve discovered how Midas, the muffler king, amassed its fortune. Tell me if it’s me or Midas that’s off base. Five years ago, Midas installed a new catalytic converter, along with a complete exhaust system, on my car. Recently, my car developed a rattle from underneath and my mechanic told me it was the catalytic converter. I called Midas and was told the converter was covered under warranty for 5 years, or 50,000 miles, whichever occurs first. Well, the 5 years was almost up, but I was way short of the 50,000 miles, so I took it in. After my car had been on the rack for an hour and a half, they told me the warranty only covered the heat shield - not the converter itself. Since I had driven 45 miles to their service center, I told them to go ahead and fix it, for which I paid $595. Afterward, I had the sinking feeling I’d been taken (nowhere does the warranty specify that it only covers the heat shield), so I wrote to their Customer Service Department. This time, the explanation I got was that the converter failed because my car’s engine was overheating. According to them, since the converter is designed to last the life of my car, there could be no other explanation for the failure. If they can use that defense, the warranty is not worth the paper it is printed on. Now, before I go to the BBB or other consumer protection agencies, please tell me if there is any merit to Midas’ explanation (either or both). To me, it is nothing but a cop out. What do you guys think? My car is a ‘96 Camry, with 106,000 miles on it. I have never seen any evidence that my car is overheating - no hot engine or check engine indicator. It doesn’t boil over or lose coolant. My fuel consumption is the same as always, and it performs as well overall as ever. Do I have to get a mechanic to check it over and certify that it is not overheating? While $600 is probably a drop in the bucket for a big company like Midas, if you multiply that $600 by the multitude of customers who have been taken by them, it amounts to enough to fill their royal coffers,

If, in your infinite wisdom, you see any merit in Midas’ cop out (I mean explanation) I’ll just drop it.

Carl Pfeiffer

I don’t see any merit in it whatsoever. They need to prove that your engine overheated if they’re going to use that claim to deny warranty coverage. Your next step should be to call your state’s attorney general’s office and file a complaint of fraudulent business practices. Wouldn’t hurt to call up whatever local TV station does the consumer advocate beat - they always like to get nice juicy “a mechanic ripped me off” stories.

The feds require a warranty on the converter, but I don’t believe that covers the heat shields. That said, they have given you some really good fiction.

Thanks for your response. My next step was to file a complaint with the Maine AG office, but wanted to do a reality check first. Thanks again.


First thing is first, you got taken by the Midas shop.

Second, catalytic converters DO NOT fail because the engine overheats.
Think about that for a moment, if you will.

The converter is constantly dealing with hot engine exhaust, which is several hundred degrees in temperature. When the exhaust gases hit the catalyst material in the converter, they have a chemical reaction with each other, which then sends the temperature of the converter several hundreds of degrees hotter.

When a car over heats, it goes from its normal coolant temperature of ~180 to 220 degrees up to 260 degrees. There is NO WAY this extra 40 degrees of heat, that has no direct contact to the converter, is going to cause it to fail.

What can cause a converter to fail?

Oil Contamination.
Fuel Contamination.
Coolant contamination.
Over heating of the catalyst due to a fuel mixture that is way too lean.

Unless your car is burning oil, or giving you horrible gas mileage, or has a check engine light that has been on for a while, I doubt you are actually having any issues.

You should contact the shop, and inform them that you are taking them to small claims court unless they refund your money, because you have proof that your converter has not failed due to the reason that they have stated.

Get your mechanic to write this up in writing for you.