Home » Car » Car Shakes At Idle But Smooths Out While Driving: Why Here!
Car Shakes At Idle But Smooths Out While Driving

Car Shakes At Idle But Smooths Out While Driving: Why Here!

When your Car’s engine is running, you may feel small vibrations. Soft vibrations, even a little noise, are entirely normal. However, it would be alarming if Car shakes at idle but smooths out while driving.

There are many causes of vehicle shaking when idling. Here are the main reasons and solutions for you when encountering this situation.

Some Causes Of Car Shakes At Idle But Smooths Out While Driving

Car Shakes At Idle But Smooths Out While Driving
To figure out how to fix the problem, you need to understand some of the underlying causes. The same goes for noise while driving.

The cause of Cv joint noise when driving straight can come from a damaged starter clamp. Meanwhile, any abnormality in the spark plugs, fuel intake system or air filter can be the cause of the vehicle shaking, such as:

Worn spark plugs

Worn or dirty spark plugs are the most common problems that cause your vehicle to vibrate abnormally. The cause of spark plug problems can come from melting electrodes, soot clinging to the electrodes, causing the spark of the spark plug to weaken. In addition, trouble can come from damaged high-voltage wires and power dividers.

When the spark plugs cannot ignite the fuel properly, your engine will also behave abnormally. Vibration at no load is one of those manifestations.

Vacuum hose disconnected

Vacuum hose disconnected

There are different types of vacuum tubes under the hood of a car. When inspecting the car, not many people pay attention to the vacuum hose. However, the problems associated with the vacuum hose are more than you think, including causing engine vibration.

Specifically, the vacuum tube plays the role of cleaning and removing exhaust gases from the engine. If the intake pipe leaks and loses connection, your engine will inevitably face problems related to dangerous emissions and fumes.

Timing belt is torn or cracked

The main timing task belt is to control the action of the piston in proportion to the opening and closing time of the valve in each cylinder. The timing belt also ensures the rotation of the crankshaft and camshafts. At the same time, the belt also helps to optimize the gas distribution process for the cylinder, helping the engine and transmission operate efficiently.

Therefore, any problem with the timing belt can cause engine noise. Even if your belt breaks completely, your Car’s engine can stop working.

Faulty fuel system

The most common problem with the fuel intake system is dirt buildup at the valve. This inevitable problem will often cause valve blockage, impeding fuel delivery. When the engine does not receive fuel continuously, complete idling vibration can occur.

Dirty air filter

When the engine is running, it is entirely normal to hear the characteristic sound of the air filter. However, if the dust clogs the air filter, causing insufficient air to enter the combustion chamber, the engine will make abnormal movement noises.

More seriously, when the filter is clogged, restricting airflow, your engine can vibrate excessively.

The intake airflow sensor is not working properly

The intake airflow sensor determines the amount of air entering the car engine and signals to the control system. From the sensor data, the control system will calculate to balance the carburetor ratio for the car engine.

When the intake airflow sensor has a problem, the most obvious harm is the reduced engine power, difficulty accelerating the Car, and even engine stall.

Motor vibration is also one of the warning signs of abnormal sensor operation.

Faulty engine mount

Motor mounts play an essential role in reducing engine vibration. As a result, you can quickly detect any minor component failure through vibration even at no load.

How To Fix This Problem?

How To Fix This Problem
Based on the main reasons above, there are two solutions when you have problems with engine vibration even when the Car is idling:

Clean the problem part

Accumulation of dirt causes spark plugs and air filters not to work as they should. As a solution, you may not need to replace the problem parts immediately. Instead, if you know how to get rid of the dirt, you’ll stop your Car’s vibrations.

Different parts of the Car have other cleaning methods. For example, you need to remove this part with spark plugs to check and clean the spark plugs with the RP7 solution. Meanwhile, it would help if you used a steam nozzle, spray from the inside to the outside to remove all the dirt.

Replace damaged parts

After a long time of operation, you need to replace accessories such as spark plugs, air filters, fuel filters to optimize the capacity of your Car. In addition, when the belt is torn, the vacuum hose is disconnected; you also need to immediately replace it to not seriously affect the engine.

Frequently Asked Questions

With the above information, you have understood the causes and solutions when Car shakes at idle but smooths out while driving. If you still have questions regarding this annoying phenomenon, here are a few answers to the most frequently asked questions.

Why does my Car shake after I change the spark plugs?

As mentioned in the previous section, replacing spark plugs is one of the ways to solve the problem of car vibration.

However, if you replace the spark plug yourself and commit some technical errors, the spark plug will likely not work as it should, and the car vibration when idling still does not disappear.

Can I fix motor mounts myself?

If you have all the tools and know what you need to do, you can replace the motor mount yourself.

Depending on the model of the car, the year of manufacture, the process of replacing the engine price will be different. Therefore, besides preparing the necessary tools, you need to refer to the repair manual specific to your vehicle.

Do spark plugs make cars run better?

Surely the correct installation of a new spark plug will result in a better driving experience. Specifically, some of the differences that you may feel include:

  • Vehicles use less fuel due to the new spark plugs that can save fuel up to 30%.
  • Smooth start.
  • Car engines run better, so there are fewer harmful emissions.


After a period of operation, your car will certainly not be as perfect as when you first owned it. Therefore it is easy to understand when Car shakes at idle but smooths out while driving.

However, instead of accepting the above inconvenience, you can ultimately find the cause and handle it. And the above instructions, along with the help of experts in the field of repair, are more than enough to get your car back to its best working condition.

Related Posts

Leave a Reply

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