If you start your car only to find out that it sounds like a jet engine roaring, you are most likely the latest victim of catalytic converter theft. And if your catalytic converter has been stolen, you might be wondering, “Can you drive a car without a catalytic converter? Or do I need a tow?“
Yes. Technically you can drive your car without a catalytic converter, however, it is not recommended other than to get your car to a qualified repair shop.
Catalytic converters are required in all 50 states for street-legal vehicles and driving without one will lead to poor performance and poor fuel economy.
Replacement costs can be upwards of $1500-3000.00+ so driving without one is tempting, especially if your car is old or you are not carrying insurance. Click here to learn more about catalytic converter theft is on the rise.
Are you a victim of catalytic converter theft?
If your vehicle’s catalytic converter has been stolen, your vehicle will make an extremely loud engine noise, especially during acceleration. It roars. And if that wasn’t enough, your vehicle will likely have poor, uneven, and often jerky acceleration due to inconsistent engine power should you try to drive it. Your check engine light will likely be on as well.
Due to the high cost of replacing a catalytic converter, or due to lack of appropriate insurance coverage, some vehicle owners will be tempted to remove the catalytic converter and replace it with a test pipe or “straight pipe”. The straight pipe solves a lot of the vehicle noise that comes with a missing converter. But unless you know how to modify the engine’s computer to address the air fuel mixture, you could still have poor fuel economy and an engine check light that won’t turn off.
Best case, you can file an insurance claim. Worst case, you will be stuck paying the repair cost.
And if you are a victim of catalytic converter theft once, especially at home, there is a high likelihood you could be a victim again if you do not take steps to protect your vehicle. Thieves know you will likely replace a stolen one.
Removing a catalytic converter for performance reasons
Some vehicle owners remove the catalytic converter to allow for free-flowing exhaust with the hope to gain additional vehicle horsepower. Keep in mind that removing the catalytic converter is illegal for street vehicles in all 50 states. Depending on the state fines can be high as well as some states require emissions or “smog” checks.
And, to get the engine running correctly, it usually requires additional engine tuning modifications.
What does a catalytic converter do?
A catalytic converter is an emission control device that is a key part of your vehicle’s exhaust system. A catalytic converter helps eliminate harmful emissions from your exhaust to help reduce air pollution.
All gas and diesel-powered vehicles manufactured after 1974 are required to have a catalytic converter installed.
How does a catalytic converter work?
The gasoline your engine burns is made up of hydrocarbons. Hydrocarbons consist of hydrogen and carbons that when burned in perfect conditions release water and carbon dioxide.
However, engine combustion is not perfect. As a result, carbon monoxide, nitrogen oxide, and other dangerous exhaust gases are created as a byproduct of combustion.
Due to environmental concerns like high pollution and smog, the catalytic converter is designed to take these harmful emissions and change them into safe gases like carbon dioxide and water.
As the harmful gases flow through a special honeycomb-like chamber, they pass through a filter containing catalyst agents. Catalyst agents consist primarily of precious metals, platinum, rhodium, and palladium. These metals react with the dangerous gas molecules flowing through the catalytic converter and as a result of this reaction, the dangerous gas molecules are split up into safer byproducts.
Will removing the catalytic converter hurt my engine?
Most mechanics will discourage you from driving your car long-term without a catalytic converter because it is a key part of your exhaust system.
Driving without a catalytic converter is a temporary solution and driving modern cars and trucks without one long-term, could lead to engine damage over time as the engine expects a certain level of backpressure coming from your exhaust system when operating normally and the engine’s computer will compensate when it isn’t there. A certain amount of drag is expected.
And, while there may not be immediate damage, you can expect reduced engine power and poor fuel economy.
Does removing the catalytic converter affect engine performance?
As we mentioned, removing the catalytic converter on a normal, street-legal vehicle can negatively affect engine performance.
Modern cars have computers that are tuned to regulate emission flow and tune engine performance through various sensors such as oxygen sensors. Removing the catalytic converter can also lead to decreased fuel economy and loss of performance.
While replacing catalytic converters is expensive, it really is the best option to stay legal, pass emissions testing, reduce exhaust sound, improve fuel consumption, and keep carbon monoxide, nitrogen oxides, and other harmful emissions output from polluting the environment.
Is removing a catalytic converter illegal?
Yes. In all 50 U.S. states removing your car’s catalytic converter is illegal.
Beyond that, if you live in a state that has emissions or smog checks, your vehicle will fail without a catalytic converter as the inspector will observe harmful exhaust gases coming out of the exhaust pipe.
If you get caught driving a vehicle without a catalytic converter (other than driving directly to a repair shop), fines could be very high depending on the laws in your state.