Check Engine Light Solutions: How to Bypass a Faulty Catalytic Converter

The check engine light could remain on even if your catalytic converter is not stolen; it could simply not be functioning correctly. No need to fret. So that it doesn’t remain on the dashboard, I will demonstrate how to disable the catalytic converter check engine light.

Check Engine Light Step-by-step Catalytic Converter with a Bypass

Perhaps your catalytic converter isn’t stolen but malfunctioning; alternatively, you can be experiencing the same issue that I did. If you’ve changed your catalytic converter for whatever reason but the check engine light is still on, you’ll need to know how to remove the code associated with the converter using a code reader.

After you remove the code, the check engine light will go out. To keep the catalytic converter check engine light from staying on while you’re using a straight pipe to bypass it, you’ll need to know how to disable the converter.

I didn’t replace the catalytic converter when mine was taken; instead, I used a straight pipe to bypass it. I did this because I was afraid someone may steal it again, and my garage wasn’t secure enough.

Instead of getting a new catalytic converter, I decided to use my catalytic converter bypass kit and fit it into the straight pipe. Still, I’ll only be giving you a rundown of the steps to do to disable the catalytic converter warning light in this piece.

Allow me to begin!

Here is the process to follow:

  • Be sure the catalytic converter is the cause of the check engine light by observing the dashboard.
  • If possible, replace the catalytic converter; alternatively, install a catalytic converter bypass kit and run a straight pipe instead.
  • After installing a new catalytic converter, make sure you clear all of the codes associated with it. If, however, a straight pipe is used instead of the catalytic converter, then go to step no. (4).
  • A spark plug defouler must be purchased once the straight pipe has been installed into the Catalytic converter’s location.
  • While a long spark plug defouler would be ideal, you will need not one but two of the shorter varieties if that is not possible.
  • The rear oxygen sensor should be unscrewed before being inserted into the spark plug defouler and secured with a screw. (top tip: before you install the spark plug defoulers, screw them together if they are short).
  • In order to ensure a snug fit after screwing the sensor into the defoulers, you may have to lightly drill one of them. When you’re done, screw the defoulers back into the exhaust.
    The light will go out once you drive around for a while or use a code reader to clear the codes.
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If your catalytic converter has an oxygen sensor, you can bypass it by following the steps outlined above. I figured out how to get around my catalytic converter in this way so the check engine light wouldn’t stay on until I found a more secure parking location, at which point I went out and bought a new one.

Advantages and disadvantages of bypassing the catalytic converter check engine light


  • It is more cost-effective to avoid replacing the catalytic converter altogether by disabling its check engine light.
  • If you simply want to turn off the light, you can do it by clearing the catalytic codes.
  • If your catalytic converter was clogged and you had a delete on it before you learned how to bypass the check engine light, you might have seen a little boost to engine power and fuel economy.


  • Ignoring the catalytic converter warning light could result in failing your state’s emissions test.
  • Even if you know your catalytic converter isn’t working, you’ll still receive the misleading impression that it is. Because of this, dangerous gas emissions will keep escaping into the atmosphere.
  • Downstream O2sensor bypass and catalytic converter deletes are against the law in the majority of nations.


Even though you eliminate the catalytic converter on purpose, the light will remain on. If the problem with the check engine light persists after following the instructions to the letter, try resetting the engine. Unfortunately, there are instances when we have no choice but to turn off the check engine light, even though doing so is not ideal owing to problems with the catalytic converter.

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