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Catalytic converter rattles can be a bad day on the road. Most motorists often view catalytic converters as both a blessing and a curse.
These devices help improve the quality of air by reducing tailpipe performance but at the same time, they add back-pressure that affects performance. This was the case of pellet-based converters but the modern ones have minimal effects on the performance of your car– that according to the Import Tuner 2006 Magazine edition.
Symptoms of a Failing Catalytic Converter
Catalytic converters help reduce vehicle emissions and pollution. It’s a metallic canister installed on your car’s exhaust system.
The canister is filled with a chemical catalyst- usually palladium and platinum mixture to help convert a vehicle’s emissions into non harmful gases.
Below are 5 symptoms of a failing catalytic converter. (*)
Rattling Noises
Rattling sounds from under your automobile is a symptom of a fault or failing catalytic converter.
If the catalytic converter becomes old or gets damaged from the honeycomb meshes inside can break apart, causing rattling noises.
The rattle can be more pronounced when starting the vehicle and worse over time.
Reduced engine performance
Another symptom of a failing catalytic converter is reduced engine performance. The catalytic converter can affect the engine performance when fault because it’s built-in the car’s vehicle exhaust system.
A cracked converter will leak very harmful gases while a clogged one will restrict exhaust flow.
Either way, it will affect the performance of your vehicle and cause a reduction in fuel economy, power, and acceleration.
Sulfur Smell
During engine combustion, hydrogen sulfide is produced and converted into odorless sulfur dioxide.
With a failed converter, you may notice a rotten egg-like smell from your exhaust pipe and at times, may cause dark exhaust smoke.
Inspect Engine Light Comes On
A failing catalytic converter can cause illuminated Check Engine Light. The air-fuel ratio sensor and an oxygen sensor in modern cars monitor the efficiency of the converter by tracking gases level in the exhaust system.
If the computer detects that the converter is not catalyzing gases properly, it will trigger Check Engine Light.
But because a variety of issues can trigger the Check Engine Light, it’s advised to have your vehicle scanned.
Failed Emission Test
Several states in the United States require a diagnostic check to pass the emissions test. A trouble code is often stored in the vehicle’s computer if the catalytic converter is faulty.
If this problem exists, your car will fail the test.
How to Quiet a Rattling Catalytic Converter
Since buying a new converter can cost you thousands, there are some ways to prolong the lifespan of your existing one. Below are several methods to help you fix a rattling converter.
1. Stop the Rattles
A failing catalytic convert will cause rattling noises. Because the gadget helps absorb toxic exhaust gases, the longer you inspect it and keep it from coming apart, the better.
You can use a mechanic’s stethoscope to find out the loose pieces in your catalytic converter.
To fix this problem, drill a hole at each location and put a drywall screw in it. The screw will help hold pieces in place and help prolong the lifespan of your catalytic converter.
2. Clean it
Inspect your converter for mild oil fouling or carbon buildup and try cleaning it. A catalytic converter cleaner will cost you less than $25, and you can mix them with your gasoline.
As you drive your vehicle, the cleaner removes harmful deposits from the converter and the engine, as well.
If this hack doesn’t solve your problem, your converter could likely be clogged with phosphorous and sulfur from your oil and fuel, respectively.
Researchers at Madrid’s Institute of Catalysis and Petrochemistry have found out that dilute citric acid will remove acid deposits without affecting the converter’s platinum.
You only need to soak your catalytic converter in citric acid for around 6 hours and if no other problems exist, your converter should be good as new.
3. Gut it
If everything else fails, there’s one more hack before replacing your catalytic converter.
You should only choose this method when the monolith substrate filling the converter is too fouled or too cracked to cleanout.
At this point, it’s only possible to unclog the converter by getting rid of the substrate filling.
Gutting the converter will help relieve the back-pressure in the exhaust and make your vehicle drivable until you get a new converter.
Firstly, unbolt the intermediate pipe from the back of the converter to expose the interior. Then insert a crowbar into the converter and bang it around.
You can hit the crowbar with a hammer from time to time to speed up the process.
Check the progress using a flashlight and use a shop vac to remove substrate pieces. Alternatively, you can idle the vehicle for a few minutes to blow out large stubborn chunks.
After a final vacuuming with a shop vac, it’s time to reconnect the intermediate pipe. It’s recommended to use a creeper and a mask for this job to avoid contact with the substrate.
Recommended Catalytic Convert for Quieter Rides
Below are some of our recommended catalytic converters. They are among industry leaders and readily available on amazon.
Eastern 70318 converter
It can fit most cars. For example, I had it installed in my 2001 and 1997 Jeep Cherokee. But it’s important to confirm whether it’ll fit your car before placing your order online.
AUOSAVER88 Converter for 1998-2002 Honda Accord
This is a direct-fit high flow catalytic converter designed to meet and also exceed quality & performance without sacrificing flow rate.
In addition, its made of heavy-duty stainless steel for maximum durability.
The converter is OBDII and federal EPA compliant backed by 50,000 miles or 5 years limited warranty.
On How To Quiet A Rattling Catalytic Converter
In conclusion, while these fixes will help you fix a rattling catalytic converter, regular maintenance will help prolong its lifespan. Your mechanic will perform all the necessary inspection- Check Engine Light Inspection to identify possible problems with your converter.