Car TalkCar MaintenanceCar NoisesReasons Why Car Makes Rattling Noise When Accelerating

Reasons Why Car Makes Rattling Noise When Accelerating

Your car can vibrate, shake, and create various types of noises for different reasons. One such problem is a car makes rattling noise when accelerating!

If it particularly happens when you accelerate the engine, you can pin down the problems on common failures of several components.

The Reasons Behind Transmission Rattling Noise When Accelerating

Anytime you find noises from your car, especially when accelerating, it’s a warning sign that your car needs to be attentive.

Although not all bad, you shouldn’t ignore it because problems can associate with a lot of things. Knowing about them will help you with quick diagnosis and finding the correct fix before it gets worse.

Here are some common causes of sounds when accelerating in cars that drivers need to know.

The transmission fluid level

It’s not a major issue, but you would want to check it to rule out the obvious cause. The fluid should exactly be at the level instructed in the owner’s manual.

A low level of fluid is one of the reasons. It’s a simple issue with a simple fix, but the consequence could be outright scary.

rattling sound when accelerating
Low transmission fluid level could be the source of the rattling when accelerating. (Photo: GM Forum)

Torque converter

A bad torque converter could be the origin of rattling sound when accelerating. It will be a faint sound when the car is idling in ‘Park’ mode, but the volume and frequency will increase in proportion to acceleration.

It could indicate the last stage of the converter’s life. If this happens, you should take the vehicle to a repair shop as soon as possible.

Motor mount

The motor mount on the passenger side could be another obvious culprit. Its failure could lead to a car makes rattling noise when accelerating. A ruptured mount will leak fluid everywhere.

So, if you see dark lines of dripping oil underneath or on the frame next to the side mount, take it to a mechanic.

Sometimes, it’s hard to determine the failure just by looking, especially if there’s no stain of oil. You will need to have it diagnosed by a professional in that case.

Read More: Transmission Fluid Changing: Everything You Need to Know

Heat shields

These components act as a thermo-reflective barrier between the exhaust system and other parts including the gas tank, fuel lines, and the cabin of a car.

When they are loose or broken, they fail to completely block the heat transfer to these key areas. As a result, you will hear frightening rattles at higher speeds.

transmission rattling noise
Check the exhaust system when the engine is off for several hours. (Photo: Brandon Gagne @ Youtube)

You have to inspect the exhaust system to find out if heat shields are causing rattling noise in car when accelerating.

However, do it only when the engine is off for several hours as the exhaust pipe and some other parts remain hot even after hours.

V-Belt pulleys

The engine of a vehicle has many belt pulley attachments. Each of these accessories uses a pulley for a drive, along with one or more sets of bearings. The purpose of the belt is to transmit power between different engine components.

They work by the friction between the belt and the pulley, which is why loose belt pulleys can cause different parts to work poorly or not at all.

The speed of these pulleys escalates with the engine speed. If they are slightly bent or loose, the metal-on-metal contact will create a terrifying rattling sound.

Open the hood and inspect the V-belts when the engine is off and running. If a pulley is bad, the belt will show damage in the form of frayed sides.

In case the accessory drive system is the root for a car makes rattling noise when accelerating, you can remove the belt and spin each of the pulleys to see if anything wobbles or feels loose.

Worn wheel bearings

In most cases, badly worn wheel bearings will make a loud noise when driving. This noise usually changes as the vehicle accelerates. At high speeds, this sound often ​reminisce a “humming” or a “rattle” sound.

Moreover, one can identify a faulty wheel bearing when cornering. If the sound in question changes in tone or stops completely while turning, the vehicle’s wheel bearings could be a suspicious cause.

Tire or wheel problems

Car tires that don’t have steady wear will definitely cause a rattling sound from engine, even as a wheel-bearing problem.

In case you notice your car tires make a sound since it can be heard from outside of the car, especially when driving with the window open.

The cause could be unsteady wear which makes a higher and lower spot. This is one of the foremost reasons that can cause your transmission rattling noise when accelerating or driving.

See More: How to Detect Brake Noises

What’s With The Rattling Sound When Accelerating At Low Speed?

So what about car makes noise at low speed on the road? The rattling noise appears when you start speeding up from 0 to maybe 30 or 40 mph and then disappear after the car speed surpasses 40 mph.

In another circumstance, when your automobile is running at low speed, the noise keeps coming out of the car engine. Moreover, you may feel your car is held back by something indefinable.

What have you done in that situation? The culprit of rattling sound mainly derives from the car engine.

The first thing you should do is check the transmission fluid level, torque converter, motor mount, heat shields, and pulleys respectively until you could find the reason.

Let’s watch the video from Scotty Kilmer to learn how to fix the rattling sound from your engine!

FAQs on Car Makes Rattling Noise When Accelerating

How do I quickly determine if the rattling noise is serious?

If the rattling is accompanied by performance loss, warning lights, or gets louder over time, it’s best to have it diagnosed immediately.

A minor loose component might not be urgent, but engine knocking, timing chain issues, or drivetrain failures can lead to costly repairs.

Why does car rattle more when going uphill?

Rattling during uphill acceleration often indicates engine strain, which could be due to a failing catalytic converter, clogged fuel injectors, or excessive carbon buildup in the engine. It may also be a sign of a worn-out timing chain.

Why does the rattling noise disappear when I let off the gas?

This suggests the noise is related to engine load. Possible causes include detonation knock, a loose exhaust component, or a worn engine mount that shifts position when torque is applied.

Why does a car rattle only at certain RPMs during acceleration?

This could be due to harmonic vibrations affecting loose engine or exhaust components at specific frequencies.

It is also indicate a worn harmonic balancer, which helps regulate engine vibrations.

Wrapping Up

So now, do you know what to do if your car makes rattling noise when accelerating? Try to follow the instructions above and you will find your problem.

If you still couldn’t find the culprit or you have any questions related to this topic, do not hesitate to leave a comment below.

Tsukasa Azuma
Tsukasa Azuma
Tsukasa Azuma is the resident car expert at Car From Japan. He owns a car repair shop in downtown Osaka, and his years of hands-on experience shine through in his informative blog posts. Tsukasa provides top-notch car maintenance tips and keeps readers up-to-date on the latest trends in the auto industry, offering a unique and insightful perspective on everything car-related. His blog has become a go-to resource for anyone wanting to keep their car in top shape.
RELATED ARTICLES

19 COMMENTS

  1. My car creates a tapping or rattling noise around 15000rpm and then white smoke. Coolant level is okay, no high engine temp, I’m confused pls help. I’ve changed timing belt, pcv, oil filter, engine oil etc but still same. Amy confused. ..what’s the problem. I’ve got a Toyota Mark 2

  2. I had the same problem with my toyota , turned out to be the WTF valve control sensor,very easy to replace. Ask your local auto parts store , most will check it for free

  3. I have Toyota Etios liva when I m driving my car and pressing accelerator my car is giving high sound including when I m increase or decrease gears also. It’s pickup is also not up to the mark . It’s 2014 model petrol version and run about 44000 kms

  4. i get a random rattleing noise when i accelerate at low speeds odd times, sound like coming from my front left wheel well but not sure. at first i thought was just my fender liner rubbing or somthing cause it sounds likemy front left wheel area but it just randomly happens so im not sure what it is really

  5. Hi there I have a 2006 Mazda 6 Grand Touring with about 131k, when u start accelerating at around anywhere from 20 to 40 miles an hour it starts makes a weird rattling sound (kind of sounds like a chain) then it goes away and some times it comes back around 60 mph.. My car also feels like it has very little power and won’t really get up and go my mechanic suggested it might be the timing chain, but I am not sure (he hasn’t looked at it yet) any thoughts on what this could be?

  6. Hi Sukasa. I have a 2007 suzuki 1.3 Ignis single drive 5 speed Manual gearbox.
    about a month ago it developed a Knocking noise that appeared to be coming from the transmision.
    this only occurs in 1st 2nd & 3rd gears, but apart from the noise the car drives normally.
    I have tried all the simple things as you suggested,but to no avail.
    I now have checked the wheel bearings and drive shafts all seem to be OK.
    So I’am now considering it must be something in the gearbox or Diff, Please advise, Thanking you, Keith

  7. Hi Tsukasa,

    Similar incident to my late father’s car which is a 2008 Honda Accord. The weird crackling sound only occurs when the car is accelerating from 0 – 40 km/h and decelerating when nearly stop ( 30 – 0 km/h ),

    Sent to the workshop multiple times to have some parts replaces but the problem is still occurring. Not sure on what to do anymore for this case.

  8. I have a Toyota Corolla 2013 going uphill on freeway ramp or any incline If I reduce speed very low then suddenly have to accelerate … I get noise from rear … feels like tires stopped rotating ..and dragging
    If I dont take foot off gas I get a loud noise (metal on metal) Mechanic is not sure, thinks it is a transmission problem.. Transmission Shop tell me not a transmission problem.

  9. I heard a tapping noise coming from my neighbor’s care, and I was curious about what could it be. It says here that low-level fluid could be one of the reasons for the rattling noise. If that is the case, I will inform him, but it would be best to take the carr to a mechanic shop.

  10. Hi,

    Toyota RAV4 second generation, making a rattling noise when turning left only on accelerating.
    Replaced right CV joint, both front struts, right sway bar link and bushing. The rattling is still there.
    Calling Toyota gurus for the opinion. Thanks

  11. My Yaris have rattling/clunking/whirring noise at very low rpm and speed especially during cold start up…The sound normally comes when clutch is engaged… After 2 months of investigating i almost gave up and i almost purchased a new clutch set as advised by 2 mechanics i went (could be release bearing or clutch spring dampener)… But good i was able to identify the root cause…

    It is just the 2 shifter cables rubbing together and the insulator on the other cable was already worn out hence the unusual sound.. i just put a soft rubber cushion between the 2 cable and problem solved…

    Really tricky there, the good thing, i didnt lose patience and didnt impulse-buy the clutch set which cost $$.

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Most Popular