Do I Really Need To Replace My Catalytic Converter

Posted in Headlight Accessories
  • I’ve been taking my 2001 Toyota Corolla to my mechanic for awhile. Wasn’t too impressed because they forgot to install the light bulb in my headlights and stupid things etc… BUT, I recently went to AAMCO and they hooked up their computer system thingy to my car and said I needed to replace my catalytic converter and an oxygen sensor (my car has been having trouble speeding up). Total came up to $900 which wasn’t too bad compared to the dealership’s price of $1500 for just the converter.

    Anyways, I like AAMCO better because I trust them and computer systems generally don’t lie. But, I took my car back to my mechanic for a second opinion before I dish out $900 bucks. They told me that I did NOT need to replace the converter or oxygen sensor. They looked at it with their EYES and said my car will be fine as long as I keep a high enough level of gas in my engine. They said my car is having trouble because I often drive with low gas levels. (This explanation doesn’t make sense to me, that’s why I’m HERE on yahoo).

    Which mechanic should I trust? Go to AAMCO and pay $900? Or my old mechanic who says nothing is wrong?

    Again: my car is having trouble speeding up, it feels like the engine drags. My check engine light has come on multiple times. No weird smells or leaks.
    AAMCO did scan for error codes, the converter and sensor were what came up. Then my mechanic scanned for error codes and said nothing came up.

    There are 4 Answers for "Do I Really Need To Replace My Catalytic Converter"

    1. Kenny says:

      Trust AAMCO? HAhahhahhahahahahahaaahhahahhhhahaha.

      Go somewhere(maybe Autozone, it’s free) to have the ‘check engine light’ scanned for the error codes. That will tell you what’s wrong with your car.

    2. Don R says:

      A bad oxygen sensor will send bad signals to the car’s computer and it will not control fuel flow properly. Those oxygen sensors are expensive, but they don’t cost $900.

      I don’t like AAMCO. I got a transmission rebuilt by AAMCO and it failed just after the warranty ended. I know somebody else who got the same thing happen as well.

      Your Catalytic convertor is probably OK, but those guys would be so happy to sell you a new one because they are very expensive. If you change the oxygen sensors- they measure the oxygen content before and after the convertor and the computer compares those two measures to determine fuel mix to the engine. You might pay a couple of hundred for the sensors and an hour’s labor to have them installed, have the computer reset and go about your business as long as the check engine light doesn’t come on again. I know it feels bad to spend $200-$300 and still wonder if the problem’s gone. You could replace every possible part for $1000 and leave feeling like if it costs so much it must be right. Truth is, when one part is bad and you change it, the problem is gone, so changing everything else is just overkill. And, whenever you use the word “thingy” it puts a big red sign on your forehead that says “Please gyp me for every last dime”.

      Go to Toyota and have the sensors replaced, then do not use Costco gas anymore. My firend’s Honda, Toyota and Jeep all came down with bad sensors from using Costco gas.

      Driving with a low gas tank did not cause this problem. Somebody who tells you that cannot be trusted. Back in 1986 there was a different issue from low gas levels in Camrys due to the fuel pick-up on the fuel pump not being long enough and when you parked on a hill the car would be hard to start. That issue was resolved long ago.

      If your car hasn’t been tuned up for a few years, you should do that- or at least change the spark plugs. That’s mostly all they do when they say they have tuned up your car, unless something is broken.

    3. Mark says:

      The only problem with driving with a low fuel level constantly is that it will prematurely wear out your fuel pump in the tank,it runs hotter when not completely immersed in fuel.A 2001 Corrola should not need a cat converter yet,maybe oxygen sensor,my 1995 Corrola has 179,000 miles on it and all I have done is a battery,altenator,timing belt at 65,000 and a starter.I build Toyota’s at the plant,wouldn’t drive anything else except an old Ford.

    4. Old Man Dirt says:

      First of all there is a good chance that there is nothing wrong with the converter or the O2 sensor. The error code just tells a trained mechanic where to start looking. A lot of car owners are tricked into replacing the cat. They sell for about 100 dollars as scrap. Now if they talk you into a new one and replace it and take it to a scrap dealer that is a lot money for the mechanics pocket.
      If you have not had a engine tune up, get one. That may solve your problems. If not have the exhaust system checked out by a independent muffler shop. An exhaust leak can also cause these errors. If you have not run a systems cleaner of injector cleaner through with a full tank of gas, do so.
      As for full tank or low tank, keep in mind that when it cools at night condensation takes place. You see it on the lawn as dew, while the gas tank as water. The gasoline does have some emulsifiers in it to absorb the water in such a way that it will not interfere with combustion. But if the tank is left low too much there may be more water in the gas tank then the emulsifiers can handle.
      I do agree that you need to find a mechanic you can trust, but AMMCO is not the place.