Skip the auto shop - Our mechanics make house calls

Q: Muffler rattling at lower RPM

asked by on

My muffler has a rattle at lower RPM. What could it be?

What you want to do is jack it up and get under there with a rubber mallet, have somebody start listening to the rattle, and hit them up with the mallet. After this, the mufflers will often no longer rattle. A lot of times, it is the catalytic converter that rattles. The catalytic converter is before the muffler.

Now, if it runs perfectly fine and no Check Engine Light is on, you can just ignore it. Because, the only way to fix it is by replacing it. So, if it is the catalytic converter, it costs an awful lot of money. But, if it is just rattling and running okay, you can live with it. The same thing goes for the muffler. If it is the muffler that’s rattling, the only way to fix it is by replacing it. So, if it runs okay, you can live with it. But, if you don’t like the noise, figure out which one is making it and then replace it.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: How long does a muffler last? How many miles it take to replace a muffler? Is theirs any difference between each muffler? (2 muffler)

There is a good chance it is the 'flex' pipe section leaking. The life of the exhaust depends on mileage, driving conditions, and where you live. Snow and icy climates rip through exhaust systems with rust and road salt. The...

Q: My 206 c230 v6 engines makes some unusual notice especially when I accelerate faster

The rattling noise may be due to the mass air flow sensor causing the engine to run leaner than it should be. This would cause the engine ping noise. You should have the engine scanned to check the mass airflow...

Q: Catalyst not ready

Hi there. The powertrain control module (PCM) monitors the performance of emissions related systems in your vehicle. In the case of the catalytic converter, it looks at the signals from the oxygen sensors to determine catalytic converter efficiency. If the...

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...