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How to Fix a Catalytic Converter

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A catalytic converter is a vital part of a well-functioning engine, which runs into problems all too often. Telltale signs of a faulty catalytic converter are rattling or clunking noises paired with smelly exhaust fumes.

We’ve put together this guide to help you understand why your catalytic convertor is having problems and the best methods to try and fix it.

How a Catalytic Converter Works

How a Catalytic Converter works

A catalytic converter is a heat-resistant ceramic filter that sits between your car’s engine and its exhaust pipe. It converts toxic emissions into less harmful gasses through oxidation.

The converter works with other emissions devices in a car to meet federal standards. However, extreme heat or pollutants may damage it. If this happens, it’ll need to be fixed or replaced.

What Can Cause a Catalytic Converter to Fail?

What can cause a Catalytic Converter to Fail

The catalytic converter takes in carbon monoxide, unburned hydrocarbons, and nitrogen oxides and converts them into carbon dioxide, water, and nitrogen through oxidation.  These harmless gasses are then released into the atmosphere.

These are the most common reasons why Catalytic Converters Fail:

  • Driving at excessively low temperatures
  • Overloading the engine by driving at high speeds for long distances
  • Physical damage after a collision with another vehicle or object
  • Improper maintenance of the exhaust system

Some damages can lead to cracks in the converter body or flange, which will allow exhaust gases to escape without being appropriately treated. These cracks might even cause an explosion within the vehicle’s exhaust system. That’s why proper maintenance of the catalytic converter is vital.

Check your converter regularly and consider replacing or repairing it if necessary.

Common Symptoms of Faulty Catalytic Converters

There are several symptoms of a malfunctioning catalytic converter:

  • the check engine light tends to come on when accelerating faster or driving at high speeds
  • You see the vehicle seems to be emitting more than usual exhaust fumes
  • the car will stall out when coming up to stop signs or red lights
  • You notice that your fuel economy has dropped by 10% or more
  • There is an unusual smell coming from under the hood of your vehicle when driving

Checking your catalytic converter

If you suspect your catalytic converter may be faulty, you should have a mechanic inspect it. They will use diagnostic tools to examine the converter’s internal parts visually.

If they find that you need to replace the converter, they will estimate how much it costs to get this done.

Can You Repair a Catalytic Converter?

Can You Repair a Catalytic Converter

Yes and no, it depends. If the damage to your catalytic converter is not too severe, you can repair it. More extensive problems will require a full replacement.

Probably the most common cause of a malfunctioning catalytic converter is excessive heat. Cracks or holes in the converter can shell off excess heat, damaging the device’s internal parts. So even if you repair the external damage, it will not work well because of the internal impairments.

It’s a lot easier to fix a catalytic converter if the problem is physical damage caused by a collision or a pothole. This kind of shock damage can often be repaired by replacing one of the converter’s components.

The best way to determine if your catalytic converter is repairable is to visit a mechanic. They will inspect it and spot any cracks in the converter that need immediate fixing.

How to Fix a Catalytic Converter Without Replacing It

How to Fix a Catalytic Converter Without Replacing It

A failing catalytic converter can cause severe damage to the engine. When this part malfunctions, your converter might not be able to break down harmful gasses.

If you want to both save money and get the best performance out of your car, here’s how to fix a faulty catalytic converter:

  • Remove the defective part, then replace it with another one
  • Remove the damaged part, clean it up, and then put it back in place
  • Replace only broken parts of the catalytic converter

Choose a remedy depending on your situation, i.e., the underlying problem, your budget, or the availability of a solution.

Some of these methods may be time-consuming and costly, depending on the extent of the damage. However, they can help extend its life span another few years until you’re ready to replace it.

Is It Worth Fixing a Catalytic Converter?

Is It Worth Fixing a Catalytic Converter

This depends on the extent of the damage. If the converter is faulty or corroded, it is probably cost-effective to replace it instead of fixing it.  If only a few components are damaged, then repair is probably cheaper.

When a catalytic converter malfunctions, you can end up with several problems:

  • First, there is the apparent issue of reduced fuel efficiency, leading to higher costs at the pump.
  • Second, the catalytic converter is essential to your vehicle’s emissions system. So, if it fails, your car could be subject to excessive emissions and other problems.
  • Third, if your converter malfunctions and the police find you with such violations, you could face severe fines.

Fixing it can be an excellent replacement alternative with so much at stake. Remember, this remedy only makes sense if the damage is repairable; and if the fix doesn’t lead to other expenses down the road.

Can You Clean a Catalytic Converter Rather Than Replacing It?

Can You Clean a Catalytic Converter Rather Than Replacing It

This depends on the kind of damage. If your converter is faulty because of a collision or because one of the parts is damaged, then cleaning it will not help. However, converters often underperform because of a build-up of residue. Cleaning in these cases can dramatically improve performance.

Method 1: Use a pipe cleaner/small wire brush

The first method is to use a pipe cleaner or other small wire brush to clean out the converter. This is a great solution if your converter has a lot of built-up residues that may be resulting in poor performance. This will obviously not help with shock damage or faulty components.

Method 2: Apply chemical solvent

The second method is to use a chemical solvent like Gumout or Seafoam on your engine. These products remove gunk from engines. But they can also clean up the carbon deposits in converters.

The downside is that they can be expensive. Plus, you may need to apply these chemical solvents severally before noticing an improvement in the car’s performance.

Method 3: Use catalytic converter cleaner

You can also use a unique compound called Catalytic Converter Cleaner. They are available at most auto parts stores.

These products dissolve away carbon deposits restoring your exhaust flow to normal.

How to Fix Catalytic Converter: Replacing a Catalytic Converter

Replacing a Catalytic Converter

If your catalytic converter is malfunctioning, you’ll need to replace it. Replacing a catalytic converter is a straightforward process.

  • The first step in replacing a catalytic converter is to remove the old one. Disconnect the car’s exhaust system and remove the muffler and tailpipes. This process gives access to the catalytic converter.
  • Next, disconnect the bolts and hold the catalytic converter down to pull it out of place. Remove all the other parts to access the converter for a rear-mounted exhaust system.
  • After removing the old catalytic converter, replace it with a new one. Your mechanic should have all the new parts ready to guarantee speedy installation.

After installation, put everything back in place before driving your car again!

What’s the Average Lifespan of a Catalytic Converter?

What's the Average Lifespan of a Catalytic Converter

A converter’s lifespan varies by car type and how you drive it (or your driving habits).

The average life expectancy for most cars is about seven years or 100,000 miles (160,000 kilometers). This life expectancy can fluctuate depending on how you drive your car and which car you have.

For example:

If you drive short trips in stop-and-go traffic with cold starts (which produce more pollutants), your converter will probably last longer than if you drive long distances at high speeds with few cold starts (which have less pollution).

Proper Maintainance Can Extend your Catalytic Converter’s Lifespan

Proper Maintenance Can Extend your Catalytic Converter’s Lifespan

Below is a list of how to fix a catalytic converter by enabling it to last longer:

1.    Avoid idling your car

Idling is bad for your catalytic converter because it allows no time for self-cleaning.

A car that idles for extended periods will build up carbon deposits inside the converter. This build-up can even lead to misfires. The longer you idle, the more likely these deposits will form.

If you need to idle your car, do it neutral and with the engine turned off.

Park on a steep hill if you don’t have an automatic transmission. This kind of parking will allow air circulation through the engine, helping it cool off.

2.    Don’t drive too fast or too slow

The most common damage mode to a catalytic converter is driving too fast or too slowly.

When you’re going too slow, e.g., when stuck in traffic, your engine works harder. This increased level produces more exhaust gases than usual. When this happens, the gases move straight into the catalytic converter.

There isn’t enough time for exhaust gases to filter through the converter before exiting the tailpipe if you’re speeding.

Either way, if an overly-taxed catalytic converter overworks too often, it may fail. Or worse yet, it might catch fire while you’re driving down the highway!

3.    Keep your car tuned up regularly.

If your car is not running well because of worn-out engine parts, it will emit more pollutants (than usual).

Change your oil regularly and at recommended intervals according to the manufacturer’s specifications. Check for these instructions in your owner’s manual.

Most cars need an oil swap every 3,000 miles or every six months.

Discover the many pros of swapping engine oil by learning the following advantages:

  • Changing oil helps keep engines running smoothly
  • makes them last longer than expected
  • reduces pollution from exhaust fumes
  • saves money by extending engine life
  • reduces harmful emissions that cause smog and acid rain

It also prolongs your spark plugs’ life span, thus preserving your converters.

4.    Use quality air intake systems

Some car owners buy aftermarket air-intake systems to improve performance and gas mileage. While this may be true, these devices also increase the pollutants released into the atmosphere.

The best way to avoid this problem is to use a high-quality filter. Reputable products like  K&N Engine Air Filter will keep out most particles while allowing cool air in through the vents.

5.    Check the oxygen sensor regularly and replace it if necessary.

The oxygen sensor sits between the exhaust manifold and the catalytic converter. It monitors the oxygen in the exhaust gases and signals the ECU if the air/fuel mixture is abnormal.

If it fails to send out such signals, your car will not be able to adjust its fuel consumption to match driving conditions. This adjustment could lead to poor performance due to engine failure or a failing converter.

6.    Replace spark plugs regularly

Sparks are responsible for igniting the fuel-air mixture inside cylinders. They improve the performance and fuel economy of your vehicle by up to 40%.

Replace sparks every 10,000 km depending on their condition and your driving habits.

What’s the Cost of Fixing a Catalytic Converter?

What's the Cost of Fixing a Catalytic Converter

A catalytic converter can cost anywhere from $200 to $1,000. The cost depends on the car type, condition, and whether you’ll need to buy a new or used one.

If you want to DIY, first know what type of catalytic converter you have and where to find it.

The most common catalytic converter is the three-way catalyst, which has three chambers:

  • one for oxidation
  • one for reduction
  • one for adsorption

These chambers sit under the car’s rear passenger seat or near the engine compartment.

The average markup to repair a catalytic converter is $450. The national average cost for a catalytic converter replacement is $350 – $500.

Final Advice on How to Fix a Catalytic Converter

It takes a little specialized knowledge to know how to fix a catalytic converter. So don’t feel discouraged if you have no clue what’s wrong with it. Take the time and search for a mechanic that specializes in these things. They’ll help you fix it in hours and at a reasonable price.

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