So you have noticed your car shaking when stopped at red light or in the park and you don’t have a clue why this happens? If yes, you’re in the right place. This guide will provide you with helpful information about this issue.
Your car shakes when stopped due to different things such as worn motor mounts, faulty spark plugs, vacuum leaks, dirty fuel injectors, worn-out timing belt, and damaged intake airflow sensors.
Below, you’ll discover more in-depth information about why your car shakes when stopped, what are the possible causes, how to fix this problem, and other related info you need to know.
Why does your car shake when stopped?
Shaking or vibrating in your car when stopped can be due to many things. The most common issue is broken or loose/disconnected motor mounts. These mounts help keep your engine in place and minimize vibrations.
But you should also consider other potential culprits as we have just mentioned above.
Let’s briefly discuss the main reasons why your car shakes when stopped:
Worn engine mounts
Engine mounts help keep your vehicle engine attached to the car structure. If these munts become weak or broken, they’re unable to hold the engine tight in its compartment, causing shaking when your car is stopped. You can find out if worn or broken mounts are behind the shaking by shifting to neutral. If the shaking reduces, that’s a sure sign that the mounts are faulty.
Bad spark plugs
When was the last time you inspected your spark plugs? Can’t remember? Well, they should be one of the key areas to check if your car starts shaking at idle. When the plugs become dirty or faulty, they can’t fire properly. In other words, they’re unable to ignite fuel in piston cylinder when you turn on the ignition. The result is engine misfire and shaking effect.
Faulty fuel intake system
if your vehicle fuel intake system is problematic, it could also be the reason behind your car shaking at idle. The intake system can get dirty or a new one can be incorrectly adjusted—in which cases it can’t supply the required amount of (clean) fuel to your car engine, making your car shake when stopped. Still at it, a worn or cracked fuel pump can also make your car vibrate at a stoplight or when parked.
Damaged timing belt
If you have a broken or loose timing belt as well as other types of belts such as serpentine and V-belts, it could also be a source of the shaking problem. When any of these belts is faulty it obstructs the rotation of fans as well as other components that connect to it, leading to noise and pulsations in your engine.
Leaking vacuum hose
Your car engine comes equipped with a variety of vacuum hoses that are connected to various engine points. These hoses help transport gases that are by-products from different parts of your car. If one of these hoses becomes damaged, loose/disconnected, or leaky, it can create various problems including making your car shake at idle. It can also cause other issues like stalling, misfires, and even a shutdown.
How do you fix car shakes when stopped?
The process for fixing your car shaking when stopped involves first finding the culprit behind this problem.
As you have just seen above, there are many possible causes, and you’ll need to take your car through an in-depth diagnosis—focusing on the key areas above—to help you find the culprit.
You can do the diagnosis on your own or you can get your mechanic to do it for you.
Most of the causes of the shaking are DIY and you can fix them on your own without the intervention of a mechanic. These include replacing bad spark plugs, cleaning/replacing fuel injectors, reconnecting loose hoses and replacing the broken ones, and replacing the timing belt.
For an issue to do with motor mounts, you may want to contact your mechanic to fix the broken mounts or replace them for you.
Luckily, fixing most of the issues we have discussed above will not cost you a lot of money.
However, if you neglect them, they may lead to more severe damages that require you to spend more.
Why your car shakes at idle but smooths out while driving?
If your case involves your car shaking at idle but smoothing out while driving, you may also be curious to know why this happens and how you can fix it.
This problem is usually caused by defective spark plugs, bad motor mounts, loose vacuum hoses, clogged fuel injectors, or worn-out timing belts.
When your car shakes at idle but smooths out while driving, we advise you to diagnose its engine and other components to help you find the cause of the shaking.
Afterward, you can go ahead and rectify the issue to avoid further damage to your car. You can do the fixing on your own if you have the skills.
However, if you doubt your skills, it’s good to book an appointment with an expert auto mechanic to fix the issue for you.
Why does your car shake when stopped with AC on?
If your car shakes when stopped with AC on, it may be a sign that your AC compressor is faulty. When it is failing, the compressor puts extra load on your car engine, and this will cause shaking.
The shaky situation when the AC is on could also be due to a dirty throttle. This part is tasked with passing and circulating air for the air conditioning unit.
However, it is prone to accumulating carbon and dirt over time which may end up disturbing its normal functioning. If the system doesn’t get enough air for circulation, it will cause shaking and screeching.
A faulty fuel injector that’s unable to disperse fuel into your car system at a controlled speed can also cause the car to shake when stopped with AC on.
However, you may want to check if the AC is the one causing the shaking when stopped by turning it off. If the shaking goes away, then the AC system is the problem and you diagnose the above-mentioned key aspects.
But if the shaking doesn’t go away after you turn off the AC, you should look at the culprits we discussed earlier that are likely behind your car shaking when stopped with the AC on.
What if your car shakes when stopped and check engine light is on?
The dreaded CEL blinking and your car shaking can make you even more worried as it could mean the reason behind your car shaking is serious and required immediate attention.
Usually, when the engine check light comes on, it means your car is experiencing cylinder misfires. A misfire simply means there’s incomplete or no combustion inside your engine cylinders. If the misfire is severe, it makes your engine shake.
The most common causes for misfires include worn spark plugs or a bad coil pack, faulty fuel injectors, jumped timing chain, a faulty mass airflow sensor, a faulty EGR (exhaust gas recirculation) valve, and wiring problems.
When you have a blinking check engine light, you should avoid driving your car further until the issue has been resolved. This will help prevent causing further damage to your car which may cost you dearly in repairs or parts replacement.If your car shakes when stopped, it could be a sign of a problem with the engine, transmission system, or idle control valve. However, this issue could also be associated with other common problems, such as car shakes when starting or when braking downhill. To learn more about these potential causes and what you can do to fix them, check out our articles on car shakes when starting and car shakes when braking downhill. These articles provide helpful tips and insights on how to troubleshoot and solve these issues, so you can ensure the comfort and reliability of your vehicle and prevent any potential damages.
Your car shouldn’t shake when stopped or idle. If it shakes, it indicates that something is wrong with your engine mounts or other components such as spark plugs, timing belts, and fuel injectors. You should take your car in for checking by a reputable mechanic so that the issue is resolved and avoid further damage to your car.
Yes, bad spark plugs can make your car shake when stopped. When the spark plugs go bad, they result in uneven fuel burning during the engine combustion process. This causes the RPMs to fluctuate, and your engine will produce loud noises in addition to shaking due to the force the engine produces to finish the combustion cycle.
If your car shakes when it is stopped, it is mostly due to bad motor mounts which are either worn out or disconnected from the engine and are unable to hold the engine in its compartment, resulting in shaking. The vibration could also be caused by bad spark plugs, clogged fuel injectors, loose or broken hoses, and worn-out timing belts.
If you’re faced with the issue of your car shaking when stopped, you should take action quickly and find the issue causing this annoying situation and rectify it quickly before it escalates into further damage. You can follow the tips we have recommended in this guide to fix your car’s shaky problem or hire a reputable mechanic to do it for you.