How to clean a catalytic converter - step by step, easy to follow (2023)

Reducing air pollution is something we should all take seriously.

As a car owner, you must do your part. This includes proper maintenance of the components that control pollutants.

In that regard, you are about to learn how to clean a catalytic converter.

In this article, we advise how to do it, both with and without uninstalling it.

We also explain why it's useful to clean it and what you need to know before you start. That includes which methods are not advisable and why.

If you're not sure if you want to do it yourself, that's fine. Find out below where to go and what you can expect to pay to have it handled by a professional.

What is a catalytic converter and why do you need to clean it?

Emission and fuel standards set by theEnvironmental Protection Agency(EPA) are strict, and rightly so. Transport in general is a major source of pollution in today's world.

The catalytic converter works to reduce toxic fumes emitted from your vehicle. The isolated chamber contains either pellets or a structure similar to a honeycomb. These are covered with a so-called catalyst.

Catalysts are any substances that can enhance a chemical reaction while remaining intact. In this process, they are usually noble orprecious metals such as platinum.

Harmful compounds in your exhaust, such ascarbon monoxide and hydrocarbons are oxidized. They emerge as carbon dioxide and water vapor, respectively. Harmful nitrogen oxides are eventually reduced to oxygen and nitrogen.

So the net result is that harmful gases and substances are converted into much less harmful substances as they pass through the catalytic converter.

Why should you clean it occasionally?

In case of uncleanness, the following can happen:

• Ineffective gas control.
• Unconverted tailpipe emissions may violate the law.
• A decrease in engine performance.
• Damage to other car functions.

Reduction of gas control

A clogged catalytic converter is not effective in controlling toxic gases. Your car will emit higher levels of emissions, possibly more than the legal level.

Law-breaking

Smoking exhaust pipescan be a serious offense in some states and without a working catalytic converter you will not pass the emissions test.In Texas you can be fined up to $350.

Performance drop

Auto parts are designed to rely on others and work in sync. Engine performance and fuel consumption decrease if the inverter is not taken care of.

Damage due to overheating

Overheating is another possible symptom that can cause damage to other vital mechanisms.

How do you know if the catalytic converter needs to be cleaned?

The symptoms associated with a faulty or dirty device can indicate many problems. It's a good idea to be on the safe sideconsult your on-board diagnostics system (OBD-II).

Once efficiency falls below 50 percent,your check engine light comes on. Use an OBD-II scanner to find out if the catalytic converter could be faulty.

Cleaning methods to avoid

There is a lot of information online about almost everything. That doesn't mean all of them are accurate or even safe to try. For the sake of your vehicle and your own, avoid these supposedly effective ways to clean the catalytic converter:

• Paint varnish or thinner in your gas tank.
• Immerse the device in strong chemicals.
• Sawing off a welded whole.

Paint varnish or thinner in your gas tank

You may have seen guides to running lacquer or paint thinner through your gas tank to unclog a catalytic converter. Many solvents are used in the automotive industry, but not in this way. It is not wise to use non-automotive products on your vehicle.

The idea behind this trick is that the solvents in the paint or thinner break down the buildup blocking the converter.

However, such products are not made to circulate in a fuel system. They will cause more trouble than they're worth by causing internal damage. Solutions for your catalytic converter or emissions system are a much safer and more effective choice.

Unit of week in strong chemicals

A harsh cleaning agent, such as a grouting gel or bleach, may be powerful enough to remove the deposits on the device. If you soak it, the chances are even higher.

Despite their effectiveness, certain chemicals can be corrosive or acidic. They can disrupt the catalytic converter or even eat through the outside.

Sawing off a welded unit

The catalytic converter is bolted or welded on. If you know what you're doing and have the tools to hand, bolts can be loosened. But sawing off the unit is another story. The risk of accidents, both for you and your vehicle, is not worth the effort.

Don't forget that it also needs to be welded back on afterwards. The best approach is to go to a mechanic and have it done for you.

Cleaning a catalytic converter without removing it: using a cleaner

This is the easiest way to clear deposits and get your emissions back to normal. A bonus is that these cleaners can also work on your fuel system and oxygen sensors.

Required equipment

• catalyst cleaner.
• Fuel (either gas station access or fuel can).

Step by step process

1. Make sure the product is compatible.
2. Buy enough for treatment.
3. Apply to your tank as directed.
4. Drive around if you need to.

Step 1: Make sure the product is compatible

Some of these detergents are only compatible with dieselofgasoline, not both. Read the label before purchasing to make sure it is suitable for your vehicle.

Step 2: Buy enough for treatment

Larger cars require higher doses of your chosen product. Check if the quantity you buy is enough for your car.

Step 3: Apply to tank as directed

Pour the specified amount of product directly into your petrol tank. You may need to have an almost empty tank, depending on the brand of cleaner.

Step 4: Drive as needed

Start your engine and go for a ride to circulate the detergent. Check out the guidelines to know how far or how long you should drive.

If it works, there will be a noticeable improvement. Symptoms such as engine misfires, smoky exhaust and slow acceleration should have improved.

Cleaning a catalytic converter by removing and soaking it

We recommend that only intermediate to advanced home mechanics attempt removal. If a cleaner didn't work, the device may be seriously clogged.

If this tactic isn't effective either, you'll have to pay for a replacement. Driving without these pollution control components is irresponsible and illegal in many states.

Required equipment

• Gloves.
• Safety glasses.
• Large container or tub.
• Degreaser for cars.
• Penetrating oil (e.g. WD-40).
• Jack and jack stands.
• Wrench (check bolt size in vehicle owner's manual or online).
• Oxygen sensor wrench.
• Buy towels.
• Pressure washer.

Step by step process

Here's an overview of what you'll be doing:

1. Let the vehicle cool down.
2. Jack up your car. (We have manuals for thathow to use a bottle jack, Afloor jackand ascissor jack.)
3. Wear your goggles and gloves.
4. Find the inverter.
5. Examine the fit.
6. Remove the oxygen sensor(s).
7. Treat the bolts with penetrating oil.
8. Loosen the bolts, backwards.
9. Remove the bolts while supporting the inverter.
10. Inspect the device.
11. Wipe it off.
12. High-pressure cleaning, only with low pressure.
13. Prepare the solution.
14. Let it soak.
15. Rinse and dry.
16. Reinstall everything.
17. Take a ride.

Step 1: Let the vehicle cool down

The exhaust pipe and related components get hot: The inverter alone can go up to 750 degrees Fahrenheit based on speed and driving conditions. Get your supplies ready while your car cools down completely.

Step 2: Jack up your car

Jack up your car so that you can comfortably stand under the exhaust. Use yourjack standsto keep it safe.

Step 3: Wear safety goggles and gloves

Protect your eyes from falling dirt and your hands from getting dirty.

Step 4: Find the converter

The device is located somewhere in the middle or at the end of your exhaust pipes. It will be in the form of a rounded or square device - hard to miss.

Step 5: Examine the fit

Is the unit welded or bolted? Remember that welding is best done by a professional mechanic.

Step 6: Remove the oxygen sensor

Carefully remove the sensor (or sensors) using your oxygen sensor wrench and set it aside.

Step 7: Treat bolts with penetrating oil

Generously apply penetrating oil to all bolts. They are probably firmly attached or partially corroded. Let the oil loosen them for a few minutes.

Step 8: Loosen the bolts, back to front

Start with the bolt closest to the end of your exhaust. Work from there. Do not remove them yet.

Step 9: Remove the bolts while supporting the converter

Hold the device so that it does not fall on the floor. Remove each bolt and set them aside so you don't lose them.

Step 10: Inspect the unit

Is it melted or do you hear rattling when you shake it? These are indicators that the part is ready and should be discarded.

You have no choice here but to get a replacement. Until it is replaced, your car should not go anywhere but to your mechanic.

If everything seems to be OK, continue to the next step.

Step 11: Wipe

Wipe the device with a kitchen towel to remove any surface residue.

Step 12: Pressure Washer: Low Pressure Only!

Set your pressure washer on low. Hose down both the inlet and exhaust pipe to remove deposits and nasty contaminants.

Step 13: Prepare the solution

Fill your container with hot water and add the degreaser to the water.

Step 14: Let it soak

Place the device in your pre-prepared solution. Let it soak for 30 minutes to an hour - you don't want to overdo it.

Step 15: Rinse and Dry

Rinse it with your pressure washer and keep it on low pressure. Place the device on a kitchen towel and allow it to dry completely. The safest bet is to leave it for at least a few hours, but the longer you can wait, the better.

Step 16: Reinstall everything

Once it's completely dry, collect your bolts. Reattach the part and your oxygen sensor (or sensors) as well.

Step 17: Go for a ride

Drive around for a while to see if there is a difference. If nothing or little has changed, replacement is in order.

Going to a professional to clean the catalytic converter: what to expect

You can visit a mechanic or a carbon cleaning center to get quotes and see what your options are:

Carbon cleaning center

These are centers that specialize in removing carbon deposits from car engines. You can take your vehicle there, they will do an inspection and then provide a quote.

They use hydrogen to decarbonise the inverter, instead of cleaning it as we described. This is not something you should try at home.

Your mechanic

Most mechanics will recommend that you use a catalytic converter cleaner or replace it. It is unlikely that they will offer to remove and clean the device.

If all cleaning methods have failed, get ready for some bad news. Replacements are far from cheap - you can expect to pay a minimum of $1,000.

Labor costs are lower than what you pay for the part itself. This is due to the precious metals in it that serve as a catalyst.

How often should you clean your catalytic converter?

Using a suitable product from time to time is cheaper than buying a new device. Aim to do this three to four times a year for heavily used vehicles.

Those of you who don't drive very often can get by with one treatment a year. All you have to do is pour the solution into your gas tank and drive around. Or have it done professionally at a carbon cleaning center. That's much easier than removing the device or paying hundreds of dollars for a new one.

Conclusion

We've shared how to clean catalytic converters, with and without removal. Still, uninstalling the device should be a last resort, not the first thing you try.

Cleaning solutions are effective and easier to use. They can extend the life of the converter by keeping it from clogging.

Now that you know how costly replacements can be, make it a priority to take care of your inverter and your vehicle in general. You want to put off buying a new one as long as possible.

We hope you found this article helpful. Do you have questions for us? Leave a comment below so we can get back to you!