How to Get Rid of Engine Noise in Car Stereo

One of the most common problems car audio enthusiasts face is the engine noise coming from the speakers.

It is characterized by a whining noise that increases every time you accelerate your vehicle and occurs more often in aftermarket car audio systems.

Although straightforward, removing this noise is a long process as it can happen for several reasons.

How to Get Rid of Engine Noise in Car Stereo

Below we’ll discuss the major causes behind this engine noise and how you can get rid of it.

1. Check Amplifier Grounding

In case you’ve recently upgraded to an aftermarket amplifier and only got engine noise afterward, the amp’s ground connection can be the culprit. When it comes to amp installation, a solid grounding is a must as it protects the amp against any electrical overload and stabilizes the voltage levels.

On the other hand, a poor ground connection will cause the amp to overheat, go into protect mode or introduce a whining noise into the car sound.

Below are some of the key tips you can follow when making a ground connection:

• The grounding point should be located as close to the amplifier as possible and shouldn’t be more than 18-inch away, in any case.
• An ideal grounding point is a screw/metal nut directly attached to the vehicle body.
• The grounding point should not have any paint on its surface.
• If you have multiple amplifiers in your car, their grounding points should be different and not located close to each other.

2. Change Head Unit Ground Location

If you’ve recently upgraded to a new head unit, its ground connection can also be the reason behind the engine noise. Therefore, we’ll have to change the ground location to see if there’s any improvement.

An aftermarket head unit is connected to the main stereo harness through a bunch of different colored wires combined to form an aftermarket wiring harness. One of these wires is the black-colored ground wire.

First of all, we’ll cut that ground wire. Then we’ll extend that wire and look for an alternate ground location nearby.

Like in amplifier grounding, any bare metal surface with no paint will be good enough. After making the ground connection, you can verify it through a multimeter.

3. Change Amplifier Location

Sometimes you can get noise if the amplifier is mounted too close to other electrical components(s) in your vehicle. Amps can have a ground loop noise if their metal casing touches any ground area of the vehicle, resulting in a whine and hum.

In case you don’t know, a ground loop is formed when system components are grounded to locations with different grounding potential. So if you’ve grounded your head unit to the cigarette lighter instead of the chassis, there’ll be a ground loop.

Similarly, if the amplifier is in contact with the grounding point and the vehicle’s main body at the same time, you get a ground loop because both of them have different grounding potentials.

Therefore, you should change your amp mounting location and have a plastic board placed underneath it to see if the noise is gone.

4. Check RCA Cable

Many times people go cheap on RCA cables which results in different problems including engine noise. These cheap wires tend to pick up signals along the signal path which may lead to engine noise in the audio. That is why you should always go for high-quality shielded RCA cables.

Another thing you need to do is make sure that the RCA cable and 12V power wire coming from the battery should pass from opposite sides of the vehicle – not the same. It’s because the 12V cable can interfere with the RCA cable, otherwise, and introduce engine noise in your car audio.

5. Install Ground Loop Isolator for Mobile Devices

Sometimes whining noise comes into the car sound if you have a mobile device as the audio source through Aux or USB connection, instead of the car head unit.

This type of connection works fine until you decide to charge your mobile device through a cigarette adapter at the same time. This creates a ground loop and you get a static or whining noise.

To prevent this, you need a ground loop isolator. It’s a simple device that has one end connected to the aux cable and the other to your phone’s 3.5mm jack.

It’s really easy to use and comes quite cheap – most models are available on amazon at roughly 10 bucks.

6. Install RCA Ground Loop Isolator

Similar to what we did above for mobile devices, we can install a ground loop isolator for the RCA cables. These RCA isolators are simple devices with one end connected to the RCA wires coming from the head unit and the other end connected with secondary RCA cables that are then connected to the amplifier’s RCA jacks.

7. Change Speaker Wires

If you’ve implemented all of the steps discussed above and are still getting the engine noise, maybe it’s time to check the speaker wires.

To confirm this, replace speaker wires and check if the noise is still there.

If there’s no noise, the issue is the speaker wires. Maybe they’re too close to another electrical component of your vehicle which is causing noise in the sound. Or maybe there’s wear ad tear over time. Or maybe you had low-quality speaker wires in the first place

Whatever the case, now it’s time to upgrade to premium speaker wires.

Bottom Line

The worst thing about any car audio problem is that there’ll be a time-consuming process diagnosing the root of that problem.

But once you’ve found that out, the remaining tasks are relatively easier.

The same is the case here. There can be multiple reasons why you’re hearing engine noise in your car audio. But once you’ve identified the root of this issue, you will able be able to remove this noise rather quickly.