Best Catalytic Converter Cleaners: Clean Engines, Smooth Rides
Keep your engine high-performance ready with regular catalytic converter cleaning
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BY Katherine Rother / LAST UPDATED ON May 13, 2019
A car or truck's catalytic converter filters out toxic chemicals and compounds such as carbon monoxide from exhaust emissions and converts them to gases that are not as harmful. During the process, the catalytic converter can clog up, and it requires regular cleaning to properly function. That's why people use catalytic converter cleaners. In our guide, you’ll learn everything you need to know to find the best catalytic converter cleaner for your needs.
One of the top products on the market, this catalytic converter cleaner is concentrated to deliver super-charged results.
- Cleans, restores, and protects the entire fuel system
- Helps restore lost power and acceleration
- Improves fuel efficiency
- Smoothes idling and improved cold start performance
- Inconvenient packaging
- Foil that seals the cap is difficult to remove, leading to
This German-made formula uses decarbonizing technology to clean a vehicle's entire exhaust system. It's compatible with both gas and diesel vehicles.
- Dissolves soot and carbon deposits and prevents noxious residue from building up
- Easy to use and maintains engine performance
- Won’t repair a damaged exhaust system, and it doesn't cure all problems
- You may need more than one can
A concentrated fuel system cleaner, this restores engine efficiency with just one treatment in new and old cars.
- Formulation made for continual use
- Synthetic lubrication included in the formulation to help your engine run more smoothly
- Reduces carbon buildup in all engine parts
- Helps clear up engine sounds
- Packaging qualm: The nozzle on the bottle is too short to properly fit into some gas tanks, which can lead to spills
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Benefits of Catalytic Converter Cleaner
- Lower emission levels. Modern catalytic converters do pretty well to keep the number of harmful gases emitted from the car’s engine to a minimum. Adding a catalytic converter cleaner to the mix reduces the engine’s emission levels even further.
- Better engine performance. Have you noticed less performance from your engine? A gunked up catalytic converter may be to blame. Using a catalytic converter cleaner regularly will help clean the fuel injection system as well as the cylinders, improving overall performance while cutting down on fuel consumption.
- Save money. Better engine performance has another benefit: it saves you money, thanks to lower maintenance and fuel costs. On top of that, you won’t have to shell out the big bucks to change your catalytic converter.
- Reduce bad smells. Some cars develop an icky smell over time caused by build-up in the catalytic converter. If your car has the signature rotten egg smell, a catalytic converter cleaner can help.
- Protect your engine. Regularly cleaning your catalytic converter has another big benefit: it’ll help protect your engine from damage. Proper fuel and exhaust flow will keep that engine running cleaner, smoother, and better, which will also cut down on maintenance costs.
- Pass emission tests. If you’ve got an older vehicle and are up for an emissions test, a catalytic converter cleaning treatment can help. The formulation knocks old gunk, grime, and other carbon-based build-ups out of the fuel system, leading to cleaner emissions.
Red Line Oil
Headquartered in Benicia, Calif., Red Line Oil has been around for over 40 years. With roots in the racing industry, Red Line later expanded into the mainstream markets as manufacturers of high-quality engine lubricants. Since then, the company has expanded again into making a number of different automotive fluids, with the Complete SI-1 Fuel System Cleaner being among its most popular products.
Founded in 1879, Chevron is among the big names in the automotive and oil sectors. With headquarters in San Ramon, Calif., Chevron has been continuing to make high-quality automotive products, among which we find the most popular catalytic converter cleaner on the market, the Techron Concentrate Plus Fuel System Cleaner.
Based in Porter, Texas, this automotive oil company prides itself in making high-quality engine oils and lubricants. With more than 200 years of collective experience in making high-performance lubricants and other automotive fluids, Royal Purple is a name you can trust. The company’s most popular product is the Max-Clean Fuel System Cleaner.
Catalytic Converter Cleaner Pricing
- Under $10: Catalytic converter cleaner at this low price point is usually a budget option. You won’t get as good cleaning as from a mid-range or high-end brand, and you might accidentally get stuck with a knock-off that can do more harm than good.
- $10 - $20: At this price point, you’re getting a good quality product that will get the job done. You’ll find a number of slightly different formulations that end up doing most of the same thing. Keep in mind that a diesel or hybrid car will need a different formulation, many of which can be found at the upper end of this price range.
- Over $20: The high-end of catalytic converter cleaners consists of big name brands and multipacks. If you’re paying more than $20 for a single bottle, you could already be paying too much, unless it’s a specialty formulation.
For regular, gasoline-powered engines, almost all catalytic converter cleaning treatments will work with your vehicle. If you happen to drive a diesel or hybrid car, however, check the engine compatibility of the cleaner you’re considering. In most cases, a more premium blend is needed for this type of specialized engine.
Full System Cleaning
The best formulations are capable of cleaning the entire exhaust system, not just the catalytic converter. Since every part of the exhaust system is integral to how well the overall system functions, your catalytic converter cleaner should be able to give the whole thing a good flush. That will keep everything working in unison.
Although the catalytic converter cleaner isn’t all that expensive, you’ll still want to make use of a great deal. This is where multipack options come in. They’re especially useful as you’ll need catalytic converter cleaner as a regular part of your car maintenance routine, saving you money in the long run.
- Additives: Some catalytic converter cleaners include additional detergent additives that you don’t need in an effort to sell at a higher price point. If you’ve got a regular gas-powered car, you don’t need anything fancy to do the job right.
- Bottle Size: Although not the most critical consideration, it’s still an important one. Catalytic converter cleaner comes in a number of bottle sizes, with 16 ounces being the most common. Anything bigger will be a waste, as the opened bottle will start to lose potency over time.
- Formulation: The labeling of catalytic converter cleaner can be a little confusing since there are a number of look-alike products out there. Keep in mind that fuel treatments and stabilizers are not necessarily catalytic converter cleaners.
Best Catalytic Converter Cleaner Reviews & Recommendations 2021
- As a general rule of thumb, you’ll want to use about one ounce of catalytic converter cleaner to one gallon of fuel. This formula makes it easy to adjust the amount you need for smaller engines, including motorcycles.
- You don’t need to have a full tank of gas to use a catalytic converter cleaner. The more important step is to use up as much of the tank as possible with the converter cleaner in it to maximize its cleaning potential.
- Older cars may benefit from more frequent catalytic converter cleaner use because they tend to produce more harmful emissions than newer vehicles.
- After using catalytic converter cleaner, fill up your gas tank completely and drive about 50 miles on highways and side streets to re-calibrate your onboard computer. This step can help clear up oxygen sensor issues among other things.
- If you’ve never used a catalytic converter cleaner before, and you’ve already driven thousands of miles, start sooner rather than later with regular catalytic converter maintenance to help reduce the chance of trouble down the line.
Q. How do I use a catalytic converter cleaner?
A: Using a catalytic converter cleaner is one of the simplest routine maintenance tasks you can perform. One 16-ounce bottle is enough to clean up a couple of thousand miles worth of gunk. Simply pour it into your semi-full gas tank and drive on that tank until it’s almost empty to make sure that most of the chemical cleaner is used up.
Q. Can I use a catalytic converter cleaner to fix a clogged catalytic converter?
A: Unfortunately, catalytic converter cleaner is not a mechanic-in-a-bottle and won’t be the end-all, fix-all to your engine troubles. If your catalytic converter is truly clogged the only way to fix the problem is to replace the converter.
Q. How does a catalytic converter cleaner work?
A: Catalytic converters do their job by filtering out and converting harmful compounds and gases in the exhaust into less harmful ones, like carbon dioxide and nitrogen. In this process, gunk can start accumulating in your catalytic converter, most of which will be carbon. A catalytic converter cleaner is a liquid chemical formulation that runs through your converter, dissolving the build-up via chemical reactions.
Q. How often can I use a catalytic converter cleaner?
A: The catalytic converter is one of the most overlooked car parts, often only getting cleaned after many thousands of miles. To get the best results from both your cleaner and your car, consider cleaning the catalytic converter every 4,000 miles or so.
Q. Do catalytic converter cleaners work in all car makes and models?
A: Catalytic converter cleaners are safe to use with all car makes and models, including older cars. However, if you drive a diesel or hybrid vehicle, make sure the cleaner you buy is compatible with your engine. How well they work depends on a couple of factors, but mainly on how much grime has accumulated within your converter. The more dirt, the fewer results. Make sure to clean your catalytic converter regularly.
Our top pick for the best catalytic converter cleaner out there is the Chevron Techron Concentrate Plus Fuel System Cleaner. It delivers consistently great results that help your engine run better.
For a budget-friendly pick, check out the OXICAT Oxygen Sensor & Catalytic Converter Cleaner.