Car Muffler Problems? 6 Most Common Problems & Solutions

A muffler or silencer is installed on all cars with an internal combustion engine. When the muffler develops a problem, it can cause a multitude of issues for your car.

You need to address the problems quickly with a proper solution, and we have listed the most common problems with their respective solutions.

This will keep your car on the road and performing in top condition.

The muffler is part of the complete exhaust system that is designed to keep fuel efficiency high, produce excellent power, and reduce the exhaust noise to acceptable levels.

#1 – Your Car is Suddenly Louder

Your muffler is meant to reduce the sound level of the exhaust exiting the car’s tailpipe.

If your quiet four-door sedan suddenly sounds like your neighbor’s rowdy two-door sports car, it may have a damaged muffler.

Unless you like hearing how loud your car has suddenly become, you’ll want to get the damage fixed to return the car back to its original sound level.

How to Fix It

How you fix a damaged muffler is dependent on the damage that has occurred. Small holes that have punctured the muffler exterior may be able to be welded closed by a local exhaust shop.

If you need to quickly fix a small hole or a crack, you may fix either with a temporary exhaust tape from a local auto parts store. It will work for a short period of time until you can have the muffler fixed permanently.

If the damage is significant enough, the best option will be to have a local exhaust shop remove and replace the muffler with a new one.

#2 – Your Fuel Economy Goes Down

The exhaust system is designed to maximize fuel efficiency and produce the best fuel economy.

A damaged muffler may contribute to a decrease in fuel economy that you will notice every time you visit the fuel station.

The more damage the muffler has, the bigger the drop in fuel mileage in every tank of fuel.

How to Fix It

One or two small holes in a muffler may not affect the fuel economy, but a larger crack or a significant hole can contribute to a decrease in fuel economy.

If the damage can be repaired, a muffler shop in your area can weld the holes or cracks closed. It should only take a few minutes to make a small repair once the car is driven into the shop.

If the muffler is significantly damaged and can’t be repaired, it should be replaced with an equivalent muffler to return your exhaust system back to its original condition. That should restore your fuel economy to its previous level before the muffler was damaged.

#3 – Your Car’s Engine Develops a Misfire Condition

Your car’s muffler provides a restriction in the exhaust system and the engine uses that backpressure to help with evacuating the combustion chamber after the combustion cycle.

When your muffler is damaged, that backpressure can be eliminated, and it may cause a misfire in the engine during the combustion process.

How to Fix It

You may feel a loss in power or your engine may stumble when it has a misfire condition. Finding the problem should be an easy task as a small hole won’t cause a significant problem like a misfire.

A large hole in your muffler from rock damage or a corrosion problem may be fixed with a patch welded or bonded over the hole.

If the metal around the hole isn’t sufficient for a weld or a bonding area, the muffler may need to be replaced by a qualified exhaust shop in your area.

#4 – Your Muffler may Become Loose

Your car may have connections in the exhaust system that use a fastener to secure the connection rather than a weld.

Over time, these fastening joints can loosen and allow the exhaust sound to become louder or allow the exhaust components to start rattling while you drive. You may hear a slight rattle or a banging from under the car if the muffler is loose.

How to Fix It

Loose components are easy to fix if a fastener can be tightened. You can use a socket and ratchet or a wrench to tighten a loose fastener.

If the loose condition is caused because of damage after hitting an object, it may require the component to be repaired or replaced.

#5 – You Detect a Strong Odor Inside the Car

The exhaust that comes from the engine is not good to breathe. It has carbon monoxide in it, and it can make you very sick.

The catalytic converters in the exhaust system are there to help burn and clean additional contaminants in the exhaust before it exits the car’s tailpipe. The tailpipe is at the rear of the car to ensure you don’t inhale the exhaust while you’re driving or sitting in traffic.

If you can smell the exhaust inside your car, you have a damaged exhaust system that needs immediate repair.

How to Fix It

If you can regularly smell exhaust fumes inside the car, you have a leak somewhere in the exhaust system. It could be near the engine, in the piping of the system, or at the muffler.

The piping is usually out of the way from hitting obstructions like manhole covers or rocks, but the muffler may not be as lucky. Finding the leak may be as easy as looking and listening under your car.

A small leak can be easily detected by listening for a strange noise while the car is running. You may also be able to see the leaking area with or without the car running.

Fixing the leak may require welding or bonding a patch over the leak. If the leak is significant, it may require a new muffler or other component to fix the problem completely.

#6 – You Find Holes in the Muffler

You may find holes in the muffler that you didn’t recognize you had. You may never smell an odor inside the car that signals a problem with the muffler.

You may never hear it rattle because it is loose, nor have a problem with a misfire condition or poor fuel economy. Holes can be sneaky and never cause a major problem.

How to Fix It

You may consider not bothering to fix holes in your muffler if they really aren’t causing a problem. Your fuel economy is still pretty good, and your car doesn’t make you sick while driving it.

Why bother with a repair?

The reason you should fix the holes is that small holes will eventually become big holes that may not be able to be fixed easily.

Holes can form because of corrosion in the muffler. The combustion process in the engine produces condensation that can collect inside the muffler and eventually cause rust to form.

This happens more with cars that aren’t driven for months at a time or with cars that aren’t allowed to fully warm up before being stored. Corrosion can also form from salt on the roads in the winter months that collect on the exhaust.

Fixing small holes may require a welded or bonded patch to cover the holes. If the holes are due to corrosion, extra steps may need to be taken to eliminate further corrosion potential.

Salt can be washed off, and the metal can be coated in rust eliminating paint to prevent corrosion from returning. If the holes have caused significant damage, the muffler and other components may need to be replaced with new parts to fix the problem.

You can also apply the same corrosion-prevention paint or coatings to the new exhaust components to protect them from having issues in the future.

If you live in an area where the roads are salted during the winter months or the salty humidity stays high all year, taking extra steps to prevent corrosion is a good idea.

Read here to find about the rust belt – Where Do Cars Rust Most Across the U.S.?

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