Can you drive without a catalytic converter?
Yes, you could temporarily drive without a catalytic converter, and it won’t damage a modern car or engine.
But in the long run, it’ll emit harmful gas, sacrifice your car’s engine performance and fuel economy, and possibly get you in trouble with the law. This applies even if your catalytic converter has been stolen.
In this article, we’ll explain what catalytic converters do and why it’s illegal to drive without one. We’ll also cover what happens if you drive without a catalytic converter, how safe it is, and some helpful FAQs.
This Article Contains
- What Do Catalytic Converters Do?
- Can You Drive Without a Catalytic Converter?
- Is it Illegal to Drive Without a Catalytic Converter?
- Is it Safe to Drive Without a Catalytic Converter?
- What Happens if You Drive Without a Catalytic Converter?
- Other FAQs About Catalytic Converters
- Why Do Catalytic Converters Get Stolen, and How Do I Prevent It?
- How Much Does it Cost to Replace a Catalytic Converter?
Let’s get started.
What Do Catalytic Converters Do?
Before exploring whether you can do without them, let’s understand what a catalytic converter does.
A modern car has a catalytic converter that rests between the car’s exhaust manifold and muffler. They turn harmful chemicals (like carbon monoxide) in your exhaust gas into carbon dioxide and water before exiting your car.
This not only reduces harmful emission trails but also improves your car’s fuel consumption and performance!
As you can see, the catalytic converter is one of your car’s most essential components.
So what would happen if you suddenly had to go without it?
Let’s find out.
Can You Drive Without a Catalytic Converter?
The short answer is yes.
Temporarily driving without a catalytic converter won’t damage your cars engine in any way. However, it may cause some performance issues.
The real question is: Why would you want to drive without one?Driving without a catalytic converter will emit harmful exhaust gas into the atmosphere.
Plus, laws around catalytic converters and emission tests are very strict (for a good reason).
Unfortunately, these laws around the emissions test still apply even if your catalytic converter has been stolen.
Let’s take a closer look at the legal angle.
Is it Illegal to Drive Without a Catalytic Converter?
Yes, it’s illegal to drive without a catalytic converter in most states of the US. However, some exceptions made by the Environmental Protection Agency (EPA) make driving without a CAT legal.
While the law differs from state to state, it’s best to play it safe and ensure your vehicle always has a functioning catalytic converter fitted. The Clean Air Act of 1970 mandates that all vehicles must be fitted with carb compliant catalytic converters from the factory.
What if your vehicle didn’t come with a catalytic converter?
We’re glad you asked.
Most cars manufactured before 1970 (when the Clean Air Act was instated) didn’t come with factory-fitted catalytic converters. For this reason, some states (like Georgia) will allow you to pass respective emission checks if your vehicle is older than 25 years.
We’ve established that it’s generally illegal to drive without a CAT.
Now, let’s explore the safety aspect.
Is it Safe to Drive Without a Catalytic Converter?
Yes, you may be physically safe driving without a catalytic converter, but you won’t be legally safe (as mentioned above).
As a critical component of your car’s exhaust system, the catalytic converter reduces air pollution. So, driving with a broken catalytic converter (or no catalytic converter at all) won’t cause a crash.
Still, you’ll want to replace it as soon as you notice you have a stolen or failing catalytic converter!
Driving without your car’s catalytic converter means you’ll expel very high concentrations of carbon monoxide — an extremely harmful emission. Most deaths caused by carbon monoxide poisoning occur while operating a vehicle inside enclosed spaces.
Plus, if you have a bad catalytic converter (clogged, broken, or faulty catalytic converter), it’ll severely hinder your car’s engine performance.
Let’s look at how driving without a cat converter affects your vehicle.
What Happens if You Drive Without a Catalytic Converter?
There are a few tell-tale signs if you have a bad catalytic converter — or if it’s just not there anymore!
Here’s what you’ll likely notice:
- Loud exhaust pipe sound: If you find your catalytic converter stolen, the first thing you’ll notice is a louder exhaust pipe noise. You’ll also notice an increase in your car’s exhaust system volume when revving the engine — which is very difficult to ignore.
- Poor performance: Without a complete exhaust system, you’ll notice a significant decrease in engine power. Weak acceleration, stalling, and lack of power on inclines are dead giveaways that you may have issues with your car’s catalytic converter.
You may also notice an illuminated Check Engine Light, which happens when your car’s ECU no longer picks up oxygen sensor readings from the exhaust.
- Strong exhaust smells: Without a catalytic converter, your vehicle may emit potent smells (as well as deadly carbon monoxide gas, which has no smell at all). If ignored, these exhaust fumes could seep into the cabin, potentially causing a deadly mistake.
- Reduced fuel economy: When your car’s ECU notices a change in the concentration of exhaust fumes from the oxygen sensor, it’ll try to mend the imbalance by altering fuel levels and exhaust flow from the cars engine cylinders.
This will likely cause your fuel consumption to increase significantly.
Additionally, if the Check Engine Light is illuminated, the ECU might restrict engine power until the error has been resolved.
- Emissions failure: Vehicles must have carb compliant catalytic converters fitted in every state. If you go for a yearly inspection without one, you’ll fail the emission test.
Still have a few doubts?
Other FAQs About Catalytic Converters
Here are answers to questions you may have about catalytic converters:
1. Why Do Catalytic Converters Get Stolen, and How Do I Prevent It?
Catalytic converters contain many precious metal components, like palladium, rhodium, and platinum. These valuable metals react with nitrogen oxide to filter out any harmful gas. They also have high resale value for a catalytic converter thief.
To make matters worse, catalytic converters have very few identifying markers except a serial number. Once it’s off your vehicle, you probably won’t see it again.
Unfortunately, if you’re the owner of a low-emissions vehicle, you’re more likely to have your catalytic converter stolen, because the CATs on these models tend to have higher concentrations of valuable metals.
While it’s illegal to pay for scrap metals with cash, some merchants unfortunately still allow their purchases.
If you’d like to prevent catalytic converter theft, there are a few ways to do it:
- Install an anti-theft device on your catalytic converter: This will trigger an alarm when the device detects any tampering with the cat converter and works similarly to a vehicle alarm system. Anti-theft alarms are the best way to prevent catalytic converter theft.
- Paint your catalytic converter: Although it’s not the most effective way to prevent catalytic converter theft, painting your CAT will add an identifying marker — and, hopefully, make it easier to track down a stolen catalytic converter.
Tip: It’s best always to have car insurance for possibilities like catalytic converter theft. While having car insurance won’t save a stolen catalytic converter, it’ll take some weight off having to replace it.
2. How Much Does it Cost to Replace a Catalytic Converter?
Due to the precious metal components inside, a catalytic converter replacement isn’t cheap. A new catalytic converter can set you back between $400-$3000 — and that’s just for the part.
Considering labor, you could end up paying at least $1000 to replace your vehicle’s stolen or faulty catalytic converter.
Driving without a catalytic converter (or with a broken catalytic converter) can cause some serious air pollution and harm to your health. As a car owner, it’s your responsibility to get your vehicle’s catalytic converter repaired or replaced, even if it’s stolen.
While a catalytic converter replacement or repair can be pricy, it’s better to get them done as soon as possible — or risk facing unpleasantries with the law and Environmental Protection Agency during your next emissions test!
When the time comes to repair or replace your catalytic converter, why not contact RepairSmith?
RepairSmith is a convenient mobile vehicle auto repair and maintenance solution with expert mechanics. We‘ll give you competitive upfront pricing plus a 12-month warranty on all repairs!
Can you drive without a catalytic converter? Yes, you could temporarily drive without a catalytic converter, and it won't damage a modern car or engine. But in the long run, it'll emit harmful gas, sacrifice your car's engine performance and fuel economy, and possibly get you in trouble with the law.What are the dangers of driving without a catalytic converter? ›
Without this component, your vehicle will no longer be filtering and reducing harmful emissions, including hydrocarbons, nitrogen oxides, and carbon monoxide. Not only is this bad for the environment, but it can also lead to harmfully poor air quality.Is it safe to drive with a bad catalytic converter? ›
A Bad Catalytic Converter Can Burn Through Overtime
If you have to deal with a fully plugged catalytic, avoid driving your car. If you notice smog coming from your car, it is best to seek professional help immediately.
While removing the catalytic converter will not harm the engine, you can expect a reduction in engine power as well as a reduction in fuel economy.Can you get sick from driving without a catalytic converter? ›
Once the catalytic converter is missing, the exhaust manifold pushes the exhaust into the outside air. This leaves you at a high risk of inhaling the exhaust while you are driving and getting sick or worse.What happens to your car if you don t replace catalytic converter? ›
If a catalytic converter develops any issues, it may have an effect on the vehicle's engine since it's installed within the car's exhaust system. If the converter gets blocked or clogged, it will restrict the exhaust flow, which will cause a reduction in the car's acceleration, power, and fuel economy.What happens if a car is missing a catalytic converter? ›
When the catalytic converter has been removed, your vehicle will make a loud roaring sound that'll get louder as you push the gas pedal. Your car might also make a sputtering sound as you change speed, or you'll notice it's not driving smoothly.How long can you ride with a bad catalytic converter? ›
How Long Can You Drive With a Bad Catalytic Converter? You can drive your car indefinitely with a partially plugged converter. But we do not advise this as it'll affect your car's performance and possibly cause problems to build (on top of releasing unprocessed exhaust gas from your exhaust pipe.)How long can you drive without replacing catalytic converter? ›
Catalytic Converters are estimated to last at least 10 years, but they don't need to be swapped out as soon as those 10 years are up. It only has to get replaced whenever you start to see these issues pop up and if it's suggested by the service technicians.How much damage can a bad catalytic converter cause? ›
What Are Potential Issues With a Catalytic Converter? Catalytic converters often last for 10 years or more, but they can become contaminated, clogged, overheated or physically damaged — leading to sluggish engine performance and, eventually, engine shutdown.
When you put something in the way of the escaping exhaust--like a muffler or catalytic converter--some of the engine's power must be used to push the exhaust through those devices. So if you remove them, more of the power can be used to make the car go. That means faster acceleration, and more miles per gallon.What does a car sound like without catalytic converter? ›
You'll notice a loud rumbling or roaring sound when you turn on the engine if your catalytic converter is missing. This sound gets louder when you hit the gas. The exhaust is not working correctly, so the vehicle also drives rougher than usual, often with a sense of sputtering as you change speed.Will my check engine light come on if I remove my catalytic converter? ›
The catalytic converter converts harmful byproducts of internal combustion to less-harmful compounds. If there's an exhaust leak letting gasses out of the system before it reaches the converter, if the converter becomes damaged or if it's missing altogether, the check engine light will activate in your dashboard.Can you get carbon monoxide poisoning from a missing catalytic converter? ›
Fumes That Make You Sick
A missing catalytic converter can also cause your vehicle's exhaust to enter the passenger cabin, especially if you have a window open. As you inhale these fumes, you will start to feel sick because you are inhaling carbon monoxide.
An exhaust system without a catalytic converter releases CO emissions ranging from 30,000 to 100,000 parts per million, increasing the pollutants in tailpipe emissions and making exhaust gas leaks that much more dangerous. Because an exhaust leak can lead to CO poisoning, it is a very dangerous situation.Can driving without catalytic converter cause a fire? ›
These symptoms precede total catalytic converter failure. If left unaddressed, they can develop into a complete failure which can result in heavy smoke and even fire from your vehicle.How urgent is a catalytic converter? ›
You should replace a catalytic converter If you do not repair or replace your car's catalytic converter in time, you risk your engine shutting down completely. The team at Performance Muffler is committed to ensuring that your vehicle performs effectively by repairing or replacing the clogged catalytic converter.What are the signs that a catalytic converter needs to be replaced? ›
- Rattling Noises. The converter, often known as the “cat”, contains a ceramic block that is covered in tiny pores rather like a honeycomb. ...
- Bad Smells. ...
- Loss of Power. ...
- Reduced Fuel Economy. ...
- Engine Warning Light.
For most modern cars, you can expect to pay around $300 – $1,650 (not including labor) for a new catalytic converter. However, these prices usually depend on the cost of the parts and local labor charges. For example, replacing a standard catalytic converter (CAT) in newer cars can cost between $500 and $2,200.What is the cheapest way to fix a catalytic converter? ›
The cheapest way to fix catalytic converter is by giving it a good clean. Furthermore, a faulty oxygen sensor can sometimes have the same symptoms as a failed converter. And in such a case, all you would have to do is simply replace the rather inexpensive sensor.
Catalytic converter theft continues to rise nationwide. Thieves can steal this antipollution device in minutes, sell it to scrap metal dealers and receive hundreds of dollars for the precious metals it contains.Why steal catalytic converters? ›
At first glance, catalytic converters seem like a weirdly specific part to steal. But there's a reason for that — they're rich in precious metals, such as platinum, palladium, and rhodium. A thief can earn a couple hundred bucks from a typical catalytic converter.Does a catalytic converter affect how a car runs? ›
When exhaust gets trapped in front of the catalytic converter, it can cause your engine to run less efficiently. This increased back pressure can actually cause your engine to stall completely. Your vehicle may jerk or act as if there is an air lock in your system.How many miles before catalytic converter goes bad? ›
The average catalytic converter is designed to last about 100,000 miles, so if your car is nearing six figures on the odometer, chances are you need to give some thought to your catalytic converter.What are the 3 most leading failures of a catalytic converter? ›
Most catalytic converter failures fall under one of three categories: Overheated, melted or broken converters.What happens if you have a hole in your catalytic converter? ›
It's not recommended to drive a vehicle with a hole in the exhaust system, especially the catalytic converter. In most cases, a hole in the exhaust can cause harmful exhaust gases to leak, which can be harmful to your health. An issue like this should be resolved as soon as possible.Can you drive long distance without catalytic converter? ›
Can you drive without a catalytic converter? Yes, you could temporarily drive without a catalytic converter, and it won't damage a modern car or engine. But in the long run, it'll emit harmful gas, sacrifice your car's engine performance and fuel economy, and possibly get you in trouble with the law.What are 2 symptoms of a failed catalytic converter? ›
Driving with A Failed Catalytic Converter
If you're noticing slow powertrain performance, reduced acceleration, a smell of rotten eggs or sulfur from the exhaust, dark exhaust smoke, or extreme heat from under the vehicle, these are symptoms of a clogged Catalytic Converter, and it should be replaced quickly.
If and when the time comes that you do have to replace the catalytic converter, it's helpful to be prepared to recognize the problem as soon as possible. Driving with a failing cat is bad for the environment, can reduce your gas mileage, and might even cause damage to other parts of the exhaust system.Is it loud to drive without a catalytic converter? ›
As we just mentioned, a missing catalytic converter will make your engine very loud. In fact, the engine will roar. You may not have realized this but the catalytic converter helps to muffle some of the engine and exhaust noise. Now that the converter is missing, your engine will be louder than normal.
What does a bad catalytic converter sound like? Often, a clogged catalytic converter sounds like a rattling noise is coming from under your vehicle and engine when you're starting, idling or driving. Excess heat or damage in the converter can break apart the honeycomb materials, resulting in the rattling noise.Does exhaust smell without catalytic converter? ›
Exhaust Has a Sulfur Smell
When your vehicle's engine is running, a properly functioning catalytic converter changes hydrogen sulfide from the gasoline into sulfur dioxide, which has no odor. When the converter fails, there may be a rotten egg-like, sulfur scent leaving the exhaust pipe.
Yes, a bad catalytic converter is a likely cause of an engine to misfire. A blocked catalytic converter will typically overheat, which can cause damage to your car's engine and result in a misfire.What does a car sound like without a catalytic converter? ›
You'll notice a loud rumbling or roaring sound when you turn on the engine if your catalytic converter is missing. This sound gets louder when you hit the gas. The exhaust is not working correctly, so the vehicle also drives rougher than usual, often with a sense of sputtering as you change speed.Why are people stealing catalytic converters? ›
At first glance, catalytic converters seem like a weirdly specific part to steal. But there's a reason for that — they're rich in precious metals, such as platinum, palladium, and rhodium. A thief can earn a couple hundred bucks from a typical catalytic converter.Can you replace catalytic converter with a straight pipe? ›
Yes, it is possible to remove an exhaust pipe without removing the catalytic converter. However, it's important to note that the catalytic converter is an essential component of your vehicle's emissions control system, and removing it can have serious legal and environmental consequences.What to do if someone steals your catalytic converter? ›
What do I do? Take your vehicle to a licensed Smog Check station to have a replacement converter installed.Will a missing catalytic converter cause check engine light? ›
Catalytic Converter Failure
If there's an exhaust leak letting gasses out of the system before it reaches the converter, if the converter becomes damaged or if it's missing altogether, the check engine light will activate in your dashboard.
American cars such as Jeep, Chrysler, Ford, Dodge, and Chevrolet are least likely to be targeted as they have less valuable converters. Nissan, Mazda, Subaru, and Hyundai also limit the amount of precious metals used in the converter designs.What states have the most catalytic converters stolen? ›
California is the state where the overwhelming majority of catalytic converter thefts occurred during this time frame—8,072. It was followed by Texas (1,705), Illinois (1,605), Ohio (1,439) and Georgia (1,215).
Stealing a converter takes just a few minutes and a battery-operated saw. "You slide under the car, slice through your exhaust system, and you're in and out usually within 30 seconds to a minute," Glawe said.How long does it take to put in a new catalytic converter? ›
Installing a new catalytic converter usually takes about one hour. Fixes for older catalytic converters tend to be simpler than modern versions, but replacing one may be more expensive depending on your car's rarity. Now that you know a few bad catalytic converter symptoms, schedule a checkup with your mechanic today.How much does it cost to install a catalytic converter shield? ›
The cost to install this protection is between $320.00 - $1000.00 depending on the vehicle. Installation does not take exceptionally long but we do request about 4 hours and that you schedule an appointment. We currently have kits available for the vehicles listed below.Can I install a catalytic converter myself? ›
If you have access to the correct tools and are confident removing the converter then you will be able to continue with the replacement yourself. If not, you will need to take your car to a garage to have a professional look at it.Do catalytic converter shields work? ›
In short, catalytic converter shields work and protect your vehicle. High-quality converter protection devices like Cat Shield™ by Miller Cat make it difficult for thieves to cut through.