Updated at: 30-05-2022 - By: Lucas

Whether you need to pass an emissions test or just want to get the most out of each tank of gas, a catalytic converter cleaner is the best way to do either. These cleaners solve common problems and can even make some expensive parts last longer.

But while the right cleaners for your catalytic converter can save you money, the wrong ones can do even more damage. So, we took the time to find and review six of the best and safest ways to clean your engine’s catalytic converter.

Even though no catalytic converter cleaner can fix every problem, these give you the best chance of getting rid of that annoying check engine light or keeping it from coming on in the first place. So, no matter what you want to do with a catalytic converter cleaner, these are the best ones.

1. CRC Guaranteed to Pass Emissions Test Formula – Best Overall

CRC Guaranteed to Pass Emissions Test Formula

The CRC Guaranteed to Pass Emissions Test Formula is a bit of a gimmick, but it does help people pass the test. But that doesn’t make the product any less good. It does a great job of making your car more fuel-efficient, faster, and cleaner overall.

It uses the most cleaning chemicals that are allowed and does a great job. But you’ll have to keep adding this product every 3,000 miles, and it won’t work on diesel engines. But if you think about the limitations, you won’t find a better cleaner on the market.


A very good cleaner

Fuel economy, speed, and emissions are all improved.

The most chemicals that can be used to clean

Guaranteed money back twice as much


Every 3,000 miles, you need to add it.

It does not work with diesel engines

2. OXICAT Oxygen Sensor & Catalytic Converter Cleaner – Best Budget

OXICAT Oxygen Sensor & Catalytic Converter Cleaner

If you want to save some money on your carb cleaner, the OXICAT Oxygen Sensor & Catalytic Converter Cleaner is a great choice. It can be used with both gas and diesel engines and has a design that cleans everything in your exhaust system.

But while this cleaner does a great job of preventing problems, it doesn’t do anything to fix them or even hide them during an emissions test. This catalytic cleaner is better used to keep problems from happening in the first place. It won’t help if you’re already having problems.


Very affordable option

Both gas and diesel vehicles can use it.

Cleaning tools with more than one use

Does an excellent job at preventing problems


Will not fix or hide problems

3. Cataclean 120007 Complete Engine, Fuel and Exhaust System Cleaner – Premium Choice

Cataclean 120007 Complete Engine, Fuel and Exhaust System Cleaner

If you are willing and able to spend a little more on a catalytic converter cleaner, Cataclean can do everything you could want and more. It not only cleans out your catalytic converter, but it also helps with rough idles, stalling, power loss, hard starts, and getting better gas mileage.

It is a very good cleaner that can be used in gas, diesel, flex-fuel, and even hybrid cars. No matter what you drive, Cataclean can make sure everything runs smoothly. Not only that, but it can also help solve small issues. Yes, it costs a little more, but it’s well worth it.


Improves fuel efficiency

It works very well as a cleaner.

Helps the engine run better

Gas, diesel, flex-fuel, and hybrid engines can all use it.


More expensive product

4. Hi-Gear HG3270s EZ Emissions Pass and Catalytic Converter Cleaner

Hi-Gear HG3270s EZ Emissions Pass and Catalytic Converter Cleaner

The Hi-Gear EZ Emissions Pass and Catalytic Converter Cleaner is another great product that will help you pass an emissions test. It cleans not only the catalytic converter, but also the rest of the fuel system.

This helps bring back lost horsepower and improve gas mileage, which could be just what you need to pass an emissions test. It does this by removing carbon deposits from everything, so don’t think it will fix a real problem with the system.

Lastly, it costs a little more than some of the other catalytic converter cleaners we looked at, but it cleans everything very well.


Cleans the fuel system as a whole

Cuts down on pollution and cleans up carbon deposits

It saves fuel and brings back horsepower that was lost.


A product that costs a little more.

5. Solder-It (CAT-1) Catalytic Converter Cleaner

Solder-It (CAT-1) Catalytic Converter Cleaner

If you think you’ll need to clean your catalytic converter on a regular basis, the Solder-It (CAT-1) Catalytic Converter Cleaner could be just what you need. Each can is priced affordably, and you can save even more by buying them in a 12-pack.

It is made to clean the catalytic converter, but it also cleans the rest of the exhaust system very well. The end result is less pollution and a smoother-running engine, which is everything you could want from a catalytic converter cleaner.

But while it works well, it’s not as good as some more expensive products. If you choose Solder-It, we suggest that you use a more expensive product the first time you use it, and only use Solder-It for regular maintenance.


You can buy in bulk

Cleans the entire exhaust system

Cleaner for the catalytic converter


Not as good as the products that cost more.

6. Sea Foam SF-16 Motor Treatment

Sea Foam SF-16 Motor Treatment

Sea Foam should be on every list of products that clean catalytic converters. But unlike what your backyard mechanic will tell you, Sea Foam won’t fix everything, and we stand by our claim that it’s not even the best product on the market.

Now, it’s very cheap and gives long-lasting results, even if they aren’t as obvious as those from cleaners made just for catalytic converters. Sea Foam has a product for both gas and diesel cars, as well as a separate product for cars that get a lot of miles per gallon.

Even though Sea Foam can be used in a lot of different ways, it doesn’t solve all kinds of problems. And while it does a good job in a lot of different areas, it doesn’t really shine in any one.


Cleans the fuel system as a whole

Very affordable

Up to two years of use

Gas, diesel, and high-mileage vehicles all have choices.


Not as good as other cleaning products

Not a cleaner for the catalytic converter

Buyer’s Guide

If you’ve never used a catalytic converter cleaner before, you might have some questions. How do these cleaners work, and are they safe to use on your car? Just as important, how do you use them, and do they work? Here, we’ll go over everything you need to know.

How To Use a Catalytic Converter Cleaner

Before using any product, you should always read the directions. After saying that, though, using almost any catalytic converter is pretty much the same.

You only need to put it straight into a full gas tank and start the engine. The chemical in the cleaner will start to work right away, but you won’t get the best results until everything has warmed up.

For the best results, we suggest letting the engine run for 5 to 10 minutes after everything has reached its highest temperature. Also, remember that you need to reset the code to turn off many check engine lights. This can be done with an OBD-II scan tool or by taking the battery out of the car for 5 to 10 minutes.

What To Expect From a Catalytic Converter Cleaner

There are a lot of reviews that trash every catalytic converter cleaner on the market because it didn’t turn off the check engine light. And despite what CRC Guaranteed to Pass Emissions Test Formula says, there is no catalytic converter cleaner in the world that can fix every problem.

The only thing these products do is CLEAN. Carbon buildup is the biggest problem with your exhaust system, so that can help with a lot of problems, but it won’t fix everything.

Think about it: if the filter elements in your catalytic converter have broken down and are now rattling around inside your catalytic converter, what is a fuel additive going to do about it?

But if your check engine light is on because an oxygen sensor has too much carbon buildup or the filter elements have too much soot, a fuel additive might be just what you need to get everything working again.

These aren’t mechanics in a can, but they could be just what you need to keep from having to take your car to a shop mechanic.

Are Catalytic Converter Cleaners Good for Your Engine?

Catalytic converters are great for your engine when they are used right. They make the car use less gas, give it more power, and even help the engine not stall. Think about it like this: when everything is stuck, nothing works the way it should.

But if you clean the parts inside your car every so often, everything starts to run a little better. It’s like putting oil on a creaky hinge; all it does is make things move a little more smoothly.

How Often Should You Use Catalytic Converter Cleaners?

Again, we suggest that you follow the directions that come with your product. Still, we know for sure that you shouldn’t use more than one catalytic converter every time you fill up. And if you do that, you should drive until your gas tank is almost empty.

If you don’t, you’ll change the amount of fuel to cleaner, which can cause problems. And even though this is the most you can put in, most of the time you’re just wasting money.

Even cleaners that need to be used the most often only need to be used once every 3,000 miles. It probably won’t hurt anything if you use it more often, but it won’t help anything either.

What To Do if You Still Have a Check Engine Light After Using a Catalytic Converter Cleaner

As we’ve already said, a cleaner for the catalytic converter won’t fix everything. So, if you’ve used the cleaner and given it enough time to work, but the check engine light still won’t go away, it means there’s a bigger problem with your car.

Depending on the engine code, the troubleshooting steps will be different, but if you don’t know where to start, it might be time to take it to a mechanic. They can tell you more about what’s going on and help you decide what’s best for your car.


Who says you have to take your car to a mechanic to fix a check engine light or pass an emissions test? For about $20, these are a cheap alternative that could save you hundreds of dollars.

No, they’re not a sure thing, but if you use them regularly, they’re sure to extend the life of some of the most expensive components in your vehicle. So, even if these don’t fix your vehicle this time, it’s a good idea to add them to your maintenance regimen to keep everything running smooth longer.