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How Long Can You Drive With A Bad Catalytic Converter?

If you have suspicions that your car has a bad catalytic converter, you may find yourself asking, “how long can you drive with a bad catalytic converter?” How long you drive your car may depend on the underlying causes and signs of a bad catalytic converter.

If a bad catalytic converter causes severe issues that prevent the vehicle from running safely, then it is best you don’t drive your car until the issues are addressed.

How Does a Catalytic Converter Work?

Catalytic Converter in how long can you drive with a bad catalytic converter

The catalytic converter is a central part of the exhaust system. It uses the process of combustion to break down three unburned gases: nitric oxide, carbon monoxide, and unburned hydrocarbons. These gasses are harmful to people and can cause smog.

The catalyst is typically made of materials like copper, platinum, and palladium.

Once the car has been started, these gasses travel through the honeycomb-like inner structure of the catalytic converter. At roughly 800 degrees Fahrenheit, the catalytic converter uses this heat to convert the toxic gasses into safer elements and compounds like water, oxygen, and carbon dioxide.

What Causes a Bad Catalytic Converter?

High mileage is a common cause of catalytic converter issues. Other causes include head gasket or intake manifold leaks, worn spark plugs, and issues with the ignition system. If the ignition does not get enough spark to the plugs, the catalytic converter cannot do its job.

The cause could be more serious, such as with a jumped timing chain or worn piston rings; these issues let air and gas out in the wrong areas at the wrong times.

What Are the Signs of a Bad Catalytic Converter?

If you are wondering how long you can drive with a bad catalytic converter, it may help to review the signs of a bad catalytic converter.

  • The engine may misfire
  • There may be an increase in emissions, often indicated by a failed emissions test
  • You may notice a decrease in performance or fuel economy
  • The check engine light may flash, especially older cars
  • You may notice an egg-like sulfur smell
  • You may notice your gas pedal has lost acceleration ability
  • Your car may be hard to start or may not start at all

How Long Can You Drive with a Bad Catalytic Converter?

The catalytic converter will typically last the duration of the car’s life. However, this is not always the case. Most problems with the catalytic converter do not stop the car from functioning. If the catalytic converter is completely plugged, you probably shouldn’t drive your car at all.

If you live in a place that requires smog checks, you will not be able to legally drive your car and will need to have the converter replaced.

Over time, if your engine is running or burning too much oil, you may notice a burning smell and possibly smoke due to the burning of the inner fiber of the catalytic converter. If this smell does not bother you, drive away. The amount of time you spend driving will affect how long can you drive with a bad catalytic converter.


car Catalytic Converter in how long can you drive with a bad catalytic converter

It is not too dangerous if you continue to drive your car despite noticing signs of a bad catalytic converter. The car can be driven as usual if only some of the parts of the converter are plugged.

As long as the catalyst is not completely plugged and you live in an area that does not require smog tests, you are likely safe to keep driving your car as long as you want.