Whining Noise When Decelerating: Causes and Fixing

You will get a whining noise during deceleration if 

  • There is low power steering fluid which can be fixed by adding more fluid and maintaining it
  • The water pump is noisy and to fix it just replace the water pump
  • There is not enough power, you can clean the spark plug or the injection pipe to fix it
  • Fuel Pump is bad, which can be fixed through replacing it

To get a detailed idea of the steps, keep reading this article. 

Why Does My Car Make A Whining Noise When I Slow Down?

There are several reasons to explain the whining sound in your car decelerating, such as it may be because of a failing water pump or your vehicle may have a problem in the engine or the driving shaft. 

Low Power Steering Fluid: 

Insufficient power steering fluid can result in whining noises when slowing down. This happens because the power steering pump has to put in extra effort when the fluid level is low. 

The pump needs enough fluid for lubrication and to generate the hydraulic force needed. The increased workload on the pump causes the whining sounds during deceleration.

Solution: Add Power Steering Fluid:

To fix this problem, just add the power steering fluid and maintain the level. Once you’ve added the fluid, double-check to make sure it’s at the “full” mark. If needed, add more until it reaches that point.

Use the correct power steering fluid for your car. You can find the right type by looking online or checking your owner’s manual for the specifications.

Be careful not to overfill the reservoir. It’s safer to have it a bit under the “MAX” line because the fluid expands when it gets hot. Avoid going above the “MAX” line to prevent any issues.

Noise From The Water Pump:

The sound is generated when your car decelerates, primarily because of the water pump. The water pump is responsible for transferring coolant to the core. Because of improper lubrication or overheating, you may get this problem in your vehicle. 

Solution: Replace the Water Pump:

To replace a water pump, follow these steps:

Gather your tools and parts: Get coolant, hose clamps, a new water pump, a timing belt kit (if needed), sealant or gasket, and any other tools required.

Drain the coolant: Find the coolant drain under the car and empty the cooling system.

Remove the old water pump: Depending on your car model, you might have to take off the fan belt, pulley, and generator to reach the water pump. Disconnect any coolant lines leading to it and unbolt the pump from the engine.

Clean the engine surface: Ensure the engine’s metal surface is clean before installing the new water pump. You can use a plastic scraper for this.

Install the new water pump: Check if the new pump needs sealant or a gasket, and apply it as required. Bolt the new pump onto the engine and reconnect any coolant lines.

Refill the coolant: Fill the cooling system with the right coolant and check for leaks.

Not Enough Power:

If you feel that your vehicle is performing very slowly, you may be having a problem with the spark plugs as they are not igniting correctly. In this case, you can solve this problem by cleaning the spark plug. 

Also, make sure that it is free from oil, carbon, and other deposits. If this does not work, get a good quality spark plug of original parts to test and check if it works.

This problem can also be due to bad fuel injection or timing chain tension, weak crankshaft position sensor, or faulty injector. 

This problem can be solved by cleaning the injection pipe or replacing it. This will also help you to fix other issues related to fuel injection.

Solution: Clean the Spark Plug:

To clean a spark plug, follow these steps:

Disconnect the spark plug wire: Before cleaning, make sure to disconnect the spark plug wire to avoid accidental ignition.

Remove the spark plug: Use a spark plug socket and ratchet wrench to take out the spark plug from the engine.

Clean the spark plug: Use sandpaper or a file to gently clean the electrode at the end of the spark plug until it looks like bare metal. A wire brush can also be used to remove debris from the threads. If needed, solvents like brake cleaner or carb cleaner can help clean the spark plug.

Check the gap: Use a spark plug gap tool to measure the gap between the plug and the electrode. Refer to your vehicle’s manual for the manufacturer-recommended gap specifications.

Solution: Clean the Injection Pipe:

To clean the injection pipe in your car, you can use a fuel injector cleaning liquid. Here’s how:

Get the cleaning liquid: Buy a high-quality injector-cleaning liquid specifically made for cleaning injector pipes.

Add cleaner to the fuel tank: Pour the recommended amount of the cleaning liquid into your car’s fuel tank. The cleaner mixes with the fuel, flowing through the injection system to eliminate carbon-based build-ups from the injector pipes.

Run the engine: Start your car and let the engine run. This ensures that the cleaning solution circulates through the fuel system and the injector pipes, effectively cleaning them.

Bad Fuel Pump:

If you face this problem, you should exchange the old one with a good quality original spare part from the local auto parts store.

Bad Fuel Pump
Source: Equipment World

A bad timing chain is responsible for having an uneven frequency and condition of the engine vibrations in your car. The condition can be bad due to wear and tear on the chains, but it may also result from a loose timing belt.

Solution: Replace the Fuel Pump:

To replace a fuel pump in your car, follow these steps:

Disconnect the negative battery cable: Ensure safety by disconnecting the negative battery cable. Also, relieve fuel system pressure by removing the fuel pump fuse or relay and starting the engine until it stalls.

Remove the fuel tank: Use a jack and jack stands to support the fuel tank. Take off the straps or bolts holding the tank, lower it, and disconnect fuel lines and electrical connections.

Take out the old fuel pump: Remove the retaining ring or bolts securing the old fuel pump and carefully take it out of the tank.

Install the new fuel pump: Place the new fuel pump into the tank and secure it with the retaining ring or bolts.

Reinstall the fuel tank: Reconnect fuel lines and electrical connections, reinstall the fuel tank and reconnect the negative battery cable.

Test the new fuel pump: Turn the ignition key to the “on” position and listen for the fuel pump to prime. Start the engine and check for any leaks.

If you want a video demonstration then check this video. 

Can Low Transmission Fluid Cause Whining Noise?

Yes, low transmission fluid can cause a whining sound in manual and automatic transmission vehicles. If you are experiencing a whining noise when you start your engine and think it is coming from the transmission area, try pouring some transmission fluid into each gear before starting up again.

This may temporarily solve your problem with these noises in and of themselves, but it is not going to fix them permanently, and you should still diagnose what is causing them. 

To test whether you have noise in your transmission, start the engine and let it warm up. Then shift through all the gears to find one that makes a distinct noise with each shift.

Next, shift that gear into first gear and give it some throttle while watching for a roar or whirring sound from under the hood. If you hear either of these, it is likely your problem is with your transmission and not something else. 

Transmission noise can be caused by many factors, almost all of which can be fixed or prevented. First, the transmission is not properly lubricated. Low fluid levels and old fluid can cause various issues in your transmission, including noises. 

Bonus: Check the guide on how to solve losing power steering fluid but no leak

Why is there a Noise when Taking the Foot Off the Accelerator?

Common causes such as worn mounts, suspension, axle shaft issues, and steering problems result in a thud sound when taking the foot off the accelerator. 

The knocking is the sound of a worn mount shaft bearing. The noise is caused by the engine shaking because it is mounted on an excessively worn mount or suspension. 

The steering rack and tie rods might also be loose. In any case, a mechanic should inspect the vehicle when experiencing this noise and fix it as needed. Does it happen all the time? Yes, you likely need new brake pads or shoes.

First, see if there is any uneven wear either in front or back of your car, and then try rotating them front-to-back to see if that helps with stopping distances. 

The part of your brake system that pushes the pads against the rotors usually has some hydraulic system to push them in and out of contact with the rotor to keep them tight against it. 

If that system gets gummed up, you may hear a thud sound too. See a mechanic if it continues after you clean the calipers out or replace the pads and shoes. 

Bonus: Find out why the car won’t start despite the power steering light on.

Why Is My Car Making A Humming Whining Noise?

The primary cause of this happening with your car is your car’s transmission. The transmission is the essential automobile part, which also needs maintenance.

If you are experiencing the vibration that comes with the noise, you surely need to look at your car’s transmission system. 

The transmission gears would likely have worn out, causing whining noises in your vehicle. Also, ensure that you care while accelerating your vehicle as it can cause problems in other automobile parts. 


In conclusion, whining noise during deceleration can be mostly due to fuel system issues which can be fixed easily through replacing a few parts and cleaning them. However, if you are not comfortable doing it yourself, consult a professional.

Similar Posts

Leave a Reply

Your email address will not be published. Required fields are marked *