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It is not normal for a car to make any kind of noise at all – whether while driving, accelerating, or idling. Any noise you hear from your car is basically caused by a broken component or a component that fell out of position. But why is your car making rattling noise when driving?
When you start hearing rattling noises as you drive, that’s a clear sign that you need to check the car for failed, loosened, and worn-out components such as loosened mounts and clamps, broken exhaust, bad heat shield, etc.
This article explains what could cause a car to make a rattling noise while you are driving.
Car Making Rattling Noise When Driving?
As a car owner, one of the ways to avoid paying too much for repair and maintenance is to identify minor issues at earlier stages.
When you discover a failing component at its earliest stage, you’d spend very little to get it fixed, and if you decide to change the component completely, that’d arguably still be affordable, compared with what you would spend if you allow the component to fail completely, and possibly damage other surrounding/connected components.
Now, below are the potential culprits causing your car to make unusual rattling noises while you’re driving or accelerating.
1. Bad Heat Shield
You probably haven’t heard about this component before right? Well, it is installed to surround the exhaust system; its function is to protect the components it is connected to, from the dangerous effects of heat radiation.
Well, heat shields don’t get damaged easily, but just like every other part/component of a car, they’re liable to fail/wear off someday, after many miles.
That said, if the heat shield gets damaged, for whatever possible reason, it can cause a rattling sound because it’d vibrate against nearby components.
2. Loosened Mounts and Clamps
There are so many bolts, mounts, clamps, etc., that are used to secure every single component in the engine bay. If a mechanic works on your car and he does not carefully fasten the mounts and clamps, most definitely, you’d be hearing rattling noise when driving.
So, if you went for an oil change, servicing, or any mechanical repair before the noise started, you need to check the mounts, screws, and clamps. There is no big surprise here, anyways, when a metallic object collides with another, vibration is bound to occur, and also, you may hear rattling noise.
3. Bad Catalytic Converter or Broken Exhaust
A bad catalytic converter can fall out of place, and thus, make a rattling noise as your drive. Also, there are other exhaust components that could cause this noise too.
So, when the rattling noise seems to be coming from underneath the car, or the rear side, it is best to check all the exhaust system components, which include the muffler, resomer, and catalytic converter.
Car Making Rattling Noise When Driving Slow
If you’re driving slow and your car is making a rattling noise, it’s a sign that you’ve got a lossy component to deal with. It could be a loose nut, mount, or bolt.
Finding the loose nut can be a bit difficult as you’d need to physically check out all the nuts to see which amongst them is loose.
Car Making Rattling Noise When Driving Fast
In most cases, when a car makes a rattling noise when you speed up, it’s because the exhaust is out of place. It’s either you’ve got a bad catalytic converter, or the aftermarket resomer you installed had fallen out of position.
Car Makes Rattling Noise When Accelerating
Rattling noise when accelerating is mostly caused by low fluids or incorrect air/fuel mixture in an engine cylinder.
So, you should first of all check the fluid levels, and then proceed to troubleshoot the engine to see if operations are going fine inside the cylinders. A bad torque converter could also be the culprit here.
How Do I Fix a Rattling Noise When i Accelerate?
You should stop the car and check all the fluids; from the power steering flow to the coolant, and the brake fluid. If any of the fluids is very low – below the recommended average – you should top it up and check if the issue is fixed.
If this doesn’t fix the issue, check the torque converter and also troubleshoot the engine cylinders to see how compression occurs in each of them. Well, this may be a technical test for you, so, you can engage a mechanic to help you out.
Summary
If your car is making rattling noise when driving, check the interior very well; maybe there’s an empty water can that fell on the floor, which is now rolling and hitting on different objects; thus, producing the rattling noise.
But if this is not the case, then you should check the components mentioned above: heat shield, mounts catalytic converter, resomer, and engine cylinders.