Four common causes for a vehicle shaking while stopped and their related parts.

If you are short on time and want to fast-track the process to professional help, click

Is Your Car Shaking While Stopped?

It commonly shakes when stopped because of loose or damaged motor mounts. However, it can also be fuel flow problems that are overstressing the engine, such as carbon deposits, faulty fuel injectors, leaking intake valves, or damaged spark plugs.

To prevent further damage and expensive repairs, it's vital to act promptly and consider having a vehicle health inspection. By doing so, you can rest assured that your car will be safe to drive and won't pose any danger to yourself or others on the road.

Watch out: If you're experiencing your car trembling when it comes to a halt, taking action is essential. This occurrence may be a symptom of an underlying problem that warrants your attention. While it may appear minor, the shaking can affect your vehicle's handling and performance, threatening road safety.

The most common causes for a vehicle shaking while driving

The most common causes for the car shaking while driving:

Leaking intake valve: The intake valve is a component that controls the amount of air that gets inside the engine during combustion. This valve works in the cylinder head, so each cylinder typically has one intake valve. However, this valve can fail, allowing too much air to enter the engine, affecting the combustion process and resulting in engine sputters and jolts.
Carbon deposits: Carbon deposits can happen inside an engine when there are too many fuel and oil residues accumulating, likely due to improper sealing. These residues accumulate and build carbon deposits, typically on components like spark plugs, valves, pistons, and cylinders. These deposits lead to engine malfunctions and sputterings.
Vacuum leak: The vacuum line or vacuum hose is a tube that uses vacuum pressure from the engine to activate various other components like the brake booster, emissions control, etc. However, if the vacuum line is leaking, allowing air to escape, the vacuum pressure becomes unstable, resulting in excess vibrations in the engine.
Faulty fuel injector: The fuel injectors constantly spray fuel inside the combustion chamber while the vehicle drives, so it can provide the needed fuel based on engine demands. However, if the fuel injectors go faulty due to wear, damage, or carbon deposits, the fuel demand won’t succeed, resulting in engine misfires and combustion-related vibrations.
Faulty spark plug: Spark plugs are components inside the engine that ignite the air-fuel mixture in the combustion chamber by creating a small electric spark. This spark causes a mini-explosion when contacting the fuel that powers the engine. However, when spark plugs fail, these sparks might lose rhythm or time, resulting in engine misfires and sputtering.
Torn torque motor mount: The torque motor mounts hold the engine, supporting it and keeping it properly aligned, specifically resisting twisting forces and engine rotations. However, due to wear, tear, aging, driving conditions, and fender benders, a vehicle’s torque motor mounts might become loose, faulty, or leaky. These issues in a motor mount lead to excessive engine vibrations since there’s no proper support.

Frequently Asked Questions

Is the "check engine" light flashing on the dashboard?

Spark plugs are a crucial part of a car's engine. They create a spark that ignites the fuel and air mixture in the engine's cylinders. This explosion produces power that forces the engine's piston down, which is necessary for the car to move. Modern spark plugs are made to last a long time, sometimes up to 100,000 miles, before needing replacement. However, the spark plugs can wear out faster if the engine gets over or underfilled with fuel. Then, oil can leak into the combustion chamber if the engine's valve seals or rings wear out. This oil causes extra carbon to build up on the spark plugs, making them dirty and malfunctioning.
Does a clunking noise come from the engine area when shifting the car into "gear?"

The motor mounts are essential parts of a vehicle that reduces the shaking and movement felt while driving. They do this by isolating the vibration from the engine through a rubber structure. However, that rubber can wear and tear down over time due to temperature changes. When you put your car into gear, it applies rotational force to the engine. If you stop the vehicle with your foot on the brake, this force is absorbed by a torque mount component. If the torque mount's rubber has torn or worn out, it'll make a noticeable clunking sound when you shift gears.
Is the "check engine" light permanently active on the dashboard?

The engine must track and control incoming air to work correctly and reduce pollution. It uses sensors to measure how much air is coming in and mixes it with fuel for efficient combustion. However, if air leaks into the engine from somewhere else (like a faulty intake gasket), the sensors will detect it and report it to the engine's computer. This will cause the "check engine" light to turn on, alarming you about a problem. This can also cause a "lean" condition, which means there isn't enough fuel in the mixture, which can cause engine damage over time.
Is the engine sputtering and shaking when the car is idle?

Fuel injectors are tiny nozzles spraying fuel into the engine's cylinders. The amount of fuel and timing of the spray is controlled electronically by the engine computer's drivers. If the electrical part of the injector fails, it won't spray any fuel into the engine, causing a "lean misfire." This means there's too little fuel in the air going into the engine, making it sputter and shake at idle. If a single injector fails, the sputtering and shaking might be unnoticeable while you're driving since the car's momentum keeps it shy. However, the engine shakes and sputters noticeably when you stop or idle.
Is the engine shuddering and shaking noticeably in cold weather?

The engine valves have an important job. They must open and close at the right time to allow fresh air into the engine and maintain the correct pressure during combustion. They also need to let combusted air out during the exhaust phase. Over time, the engine part where the exhaust seats stand may wear down. This happens because the exhaust seats are rigid while the engine head is softer aluminum. As a result, the exhaust seats can be forced into the head, causing the valve to stay partially open when the engine is cold. This makes the engine shake and misfire. However, once the engine heats up, the head expands enough to close the valve and stop the misfire.
Have you noticed a drop in the vehicle's fuel economy?

In modern direct injection engines, there's a tendency to accumulate carbon buildup and deposits. This happens because oil vapors from the crankcase don't wash away the carbon buildup from the valves and cylinder. However, engines that mix fuel with air do not have this issue. As the carbon buildup on the cylinder and valves increase, it blocks airflow, reducing the engine's efficiency and consuming more fuel. This leads to a decrease in the engine's fuel economy.

Typical fixes to address the cause(s)

These are typical processes and repair services that fix a check engine light issue

The most common cause: Faulty engine mounts

The most common reason for a car shaking while stopped is due to faulty engine mounts. The mounts that support the engine, keeping it aligned and tightly in place can loosen up, get leaky, bent, or break. In any case, if the engine mount loses balance, the engine loses support. Consequently, the vibrations that come from the engine combustion process will cause extra shakiness since the engine loses mount support.

Symptoms it causes: Apart from the vehicle shaking while stopped you might notice the check engine light on, engine misfires, engine overheating, lawnmower sounds, banging and grinding noises, etc.
High risk of priority: A loose motor mount can quickly snap away, resulting in major damage in the engine compartment that might lead to engine stalling and a complete breakdown.

How exactly do the engine mounts fail?

Engine mounts are typically sturdy and reliable, made to last for decades. However, depending on driving conditions and recent accidents or improper restorations, the mounts can become unreliable and prone to bending and loosening up. If the mounts become loose, the engine loses support, resulting in excess vibrations, even when having the car at a standstill (idle).

Go safe: Ask for a mechanic to inspect your vehicle’s engine system to investigate if the engine mounts are faulty due to surrounding components and if there’s further damage to check out. Many shops do transparent vehicle inspections and lay out your options after investigating your vehicle’s conditions.

What’s a vehicle inspection? It’s “detective work” on your vehicle, checking its systems to see if anything prevents the car from working as expected. In this case, mechanics examine different parts of your vehicle to track if anything is causing the engine mounts to get faulty. They’ll also check the condition of components during their inspection, noting which are causing the problem and which got affected by it, recommending to replace them in order of priority.

Transparency example in a loose motor mount service

An engine system inspection is the most transparent process to understand why your vehicle’s engine mount is faulty. This is because many components surrounding the engine, support mounts, and combustion components can have a say in the issue, indicating the real culprits that caused it all.

A customer brought their vehicle to the shop, concerned the car was shaking unusually while idling. They also noticed a strange noise from under the hood when shifting gears.

During a test drive, the technician confirmed that a clunking noise came from the engine bay when shifting between forward and reverse. However, the technician found nothing related to the customer's concerns during a vehicle health inspection.

To investigate further, the technician had an assistant start the vehicle while pressing the brakes with the emergency brake pulled. The technician then had the assistant shift the car between drive and reverse while torquing the engine attached. The technician noticed the engine rotating back and forth at this point and discovered that the upper engine torque mount was torn.

In addition, the front engine mount and both side mounts were sagging and transferring engine vibration to the chassis. As a result, the technician concluded that replacing the broken motor mounts was necessary.

Torn torque motor mount

In this case, the mechanic put the “Immediate Action” tag on the engine mount.

Similar Symptoms

Below are just a few examples of typical Symptoms and Fixes your car might be experiencing

Four common causes for a vehicle shaking while driving and their related parts.

Is Your Car Shaking While Stopped?

The most common causes for a vehicle shaking while driving

Frequently Asked Questions

Is the "check engine" light flashing on the dashboard?

Does a clunking noise come from the engine area when shifting the car into "gear?"

Is the "check engine" light permanently active on the dashboard?

Is the engine sputtering and shaking when the car is idle?

Is the engine shuddering and shaking noticeably in cold weather?

Have you noticed a drop in the vehicle's fuel economy?

Typical fixes to address the cause(s)

The most common cause: Faulty engine mounts

How exactly do the engine mounts fail?

Transparency example in a loose motor mount service

Similar Symptoms

Why Is My Car Shaking While I drive?

Why Is My Car Shaking When Idle?

Why Does My Car Shake When I Brake At High Speeds?

Why Is My Car Shaking At High Speeds?

Why Is My Car Shaking When Accelerating?