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Kia Soul Shaking When Idle – What Could Be Wrong?

If your Kia Soul is shaking when idling, it can raise some concerns. What could be wrong with your vehicle that would cause this issue? We have laid out the possible culprits to this issue in this article.

If your Kia Soul is shaking when idling, it could be due to the following:

  • Vacuum Leak
  • Worn Spark Plugs/Wires
  • Faulty Ignition Coil
  • Loose Engine Mounts
  • Faulty Fuel Injectors
  • Bad Timing Belt
  • Clogged Air Filter
  • Bad Oxygen Sensor
  • Bad Mass Airflow Sensor
  • Faulty Throttle Position Sensor
  • Head Gasket Leaks
  • Malfunctioning Fuel Pump
  • Bad Catalytic Converter
  • Bad Throttle Valve
  • Bad Engine Coolant Temperature Sensor

We understand the list above can be intimidating but don't worry. This article will look at each of these possible mechanical errors and help you diagnose them. In addition, we will discuss and answer other frequently asked questions about the Kia Soul, so read on!

Before you continue reading, let us say we hope you find the links here useful. If you purchase something through a link on this page, we may get a commission, so thank you!

The Kia Soul EV concept on display at the Chicago Auto Show media, Kia Soul Shaking When Idle - What Could Be Wrong?

Kia Soul Shaking When Idle - What Could Be Wrong?

When you are having mechanic problems with your vehicle, it can put a stop to your plans and be a scary situation. For example, if your Kia Soul is shaking when idling, it can cause some concern.

Let's take a closer look at the common reasons why this is happening:

The presentation of Kia Soul on the motor show

Vacuum Leak

A vacuum leak is potentially the most common reason for a Kia Soul shaking when idling. A vacuum leak can cause your engine to either run poorly or not at all. In addition, a vacuum leak will sometimes make a hissing noise coming from the engine bay.

Worn Spark Plugs/Wires

If your Kia Soul is running poorly and shaking when idling, your spark plugs or wires are the next possible culprit. Spark plugs and wiring can wear out over time.

Worn spark plugs or wires will cause your engine not to run as efficiently as it should, which will result in shakiness when at idle. If you haven't changed your spark plugs and wires in a while, this could be the issue.

Faulty Ignition Coil

A faulty ignition coil could also be the cause of your Kia Soul shaking when idling. The ignition coil sends the electricity to the spark plugs, and if there is a failing issue, it can cause your vehicle to shake when idling.

Loose Engine Mounts

Engine mounts are rubber hoses that hold your engine steady. If the engine mounts are loose, it will allow the engine to move around, which can cause shakiness when at idle.

Faulty Fuel Injectors

If you have problems with your Kia Soul shaking when idling, one of the first suggestions is to check your fuel injectors. Faulty fuel injectors will cause an engine to shake at idle. However, if the problem is severe enough, you will notice it when taking off.

Bad Timing Belt

Another reason for your Kia Soul shaking when idling is a bad timing belt. A loose timing belt can cause the engine to shake at idle and run poorly.

However, you will notice that the check engine light also illuminates in conjunction with these issues. Check under your hood to see if the timing belt is still in place and not broken.

Clogged Air Filter

A clogged air filter is also one of the causes for having a Kia Soul shaking when idling. A clog in your air filter will cause your engine to run poorly or not at all as it will be unable to get enough oxygen due to the restriction. Remove your air filter and check for an immense amount of debris and dirt.

Bad Oxygen Sensor

If your Kia Soul is shaking and sputtering at idle and the check engine light also comes on, it could be a faulty oxygen sensor. Replacing an oxygen sensor will solve this problem. In addition, you can check the O2 sensor with a vehicle code reader to see if it is the source of your problem.

Bad Mass Airflow Sensor

A bad Mass Airflow Sensor can also cause your Kia Soul to shake when idling. The Mass Airflow Sensor monitors the incoming airflow into the engine. If it fails, you will notice that your engine is not running efficiently, which leads to shaking and sputtering at idle.

Faulty Throttle Position Sensor

A faulty throttle position sensor can also cause your Kia Soul to shake when idling. The throttle position sensor is used in the electronic throttle control system and regulates the throttle cable. You will notice that when this goes bad, it will affect how you take off from a stop.

Head Gasket Leaks

A blown head gasket or cracked cylinder head are issues that typically cause a Kia Soul shaking when idling.

A blown head gasket can cause engine oil to mix with the coolant, which will result in an overheating problem for your vehicle. In addition, you will notice leaking from your radiator cap or white smoke coming out of the tailpipe.

Malfunctioning Fuel Pump

If your Kia Soul is shaking when idling and the check engine light is on, then it could be a bad fuel pump. A faulty fuel pump will not supply enough pressure to keep up with your vehicle's demand which can cause issues with your vehicle running poorly or not at all. The best way to fix this issue is to replace the fuel pump.

Bad Catalytic Converter

A faulty catalytic converter is another reason for your Kia Soul shaking when idling. This will cause the engine to run poorly and decrease gas mileage which can be noticed in many ways, such as sluggishness or bucking when accelerating.

Bad Throttle Valve

A bad throttle valve assembly can also cause your Kia Soul to shake when idling. This will cause the idle speed to increase, which causes your engine to vibrate and shake at idle. You will notice this issue in conjunction with fuel economy issues such as sluggishness or poor acceleration.

Bad Engine Coolant Temperature Sensor

A bad engine coolant temperature sensor can cause your Kia Soul to shake when idling. This is because the engine will overheat, which results in shaking and sputtering at idle.

Why Does My Kia Soul Shake?

blue Kia Soul is parked on the street on a warm autumn day against the backdrop of a street

If your Kia Soul is shaking when it is idling, it could be due to a problem with one of the mechanical parts mentioned above. In addition to the list above, if it is shaking when you are driving, it could be due to the following:

Unbalanced Tires

An unbalanced tire can cause your Kia Soul to shake when driving down the road. Also, the tire being out of balance will wobble at certain speeds, affecting how your car handles.

Front Wheel Alignment

A front wheel alignment is another common reason for an uncomfortable ride and shaking when driving. This will affect how your car maneuvers and cause uneven wear on your tires.

Bad Wheel Bearings

Bearing Symptoms Damaged

Bad wheel bearings are another possibility for your Kia Soul shaking when you are driving down the road. This will mess with the suspension system if they have gone bad, leading to poor handling and jittery steering.

Bent Rim

If your Kia Soul is shaking when driving down the road and you have recently hit a pothole or curb, then it could be due to a bent rim. This will cause an imbalance in your tires, affecting how well your vehicle handles when driving.

Incorrect Tire Pressure

Incorrect tire pressure is another common reason for a bumpy ride. If your tires are underinflated, this will affect the weight distribution, which can cause your Kia Soul to shake when driving down the road.

You will know that your tire pressure is incorrect if you notice an unusual amount of wear on one side of the tire. For example, the outside or inside shoulder will be worn more than the other side.

Bad U-Joints

Bad U-Joints are another potential cause for an uncomfortable ride and can also cause your Kia Soul to shake when driving down the road. If they have gone bad, this will affect how smoothly your vehicle drives, affecting how well it corners at high speeds.

Faulty Axels

A faulty axle can lead to vibrations when driving your Kia Soul. This is because the axles transmit power from the engine to the wheels, making them an integral part of acceleration, cornering, and braking.

Is It Safe to Drive When Your Car Is Shaking?

If your Kia Soul is shaking, it may be best to pull off the road and park somewhere safe. Shaking at idle could be small; however, it can also indicate more severe problems like bent rim or faulty axles.

Either way, you do not want to take the chance of driving your car on the highway when it is shaking. If your Kia Soul is shaking when you drive, this could be due to a problem with one of the mechanical or electrical parts mentioned above.

Shot of a man calling roadside assistance after breaking down

Why Does My Kia Soul Idle Rough?

As mentioned in this article, there are many reasons why your Kia Soul idles rough. The most common reasons are dirty fuel injectors, clogged fuel filters, air filters, various exhaust problems, and worn spark plugs. However, it could be something else that a mechanic will need to inspect and diagnose on your behalf.

Final Thoughts

Stony Stratford, Bucks, UK - November 21st 2021. 2009 orange Kia Soul

It's no secret that there are a lot of mechanic parts to make a vehicle run correctly. However, if your Kia Soul is shaking when idling or driving, it could be due to one or more of these parts, and you must diagnose the symptoms correctly.

For more articles like this one, check these out:

Can You Drive With The Powertrain Light On?

Rattling Noise In Car When Accelerating—What Could Be Wrong?

Car Shakes When Turning And Accelerating—What Could Be Wrong?