Car Jerks When Ac Is On: Causes, Signs & Fixes

Are you facing the issue, car jerks when AC is on? There are a few reasons you may be experiencing this malfunction. For example, the causes could be a damaged compressor, electrical issues, or low refrigerant.

Regardless, as a do-it-yourself enthusiast, identifying the causes and proffering the right solution is equally important.

In this article, I will discuss how to pinpoint these causes through their symptoms and how fixes to car jerking when the air condition is on.

car jumps when ac is on

Causes of Car Jerks When Ac Is On

There is no singular cause of car jolting when you turn on your AC. Car jerks when AC is on may result from a faulty compressor, bad engine mount, low refrigerant levels, a malfunctioning AC clutch, or a worn-out serpentine belt. Insufficient engine power or a clogged air filter can also contribute. We will identify these causes and their symptoms in subsequent paragraphs.

1. Damaged Motor mount

If you are experiencing violent shaking, especially when the Air conditioning is on, it may be that the motor mount, or what you call the engine mount, is damaged. These mounts (Usually three or more, depending on the car) are designed to support the engine and absorb the engine’s vibration.

2. Defective AC Compressor

The engine drives the compressor via the serpentine belt to compress refrigerants. However, if the compressor is damaged, it impacts the engine’s performance by causing more strain. Simply put, the engine works twice as hard, causing irregular power distribution and the reason the car jumps when ac is on.

3. Bad AC Clutch

The Ac clutch engages and disengages the compressor, saving fuel and energy.  However, a damaged clutch means causes irregularities in the compressor performance. In some cases, the compressor may overwork, causing an overload on the engine. Furthermore, a bad clutch can cause the compressor to engage and disengage erratically, causing jolting. You want to make sure you inspect the clutch system.

4. Poor Engine Performance

 Your Ac compressor performance relies on the engine to work effectively. Now, if the engine is not functioning optimally, the compressor becomes overloaded and causes the engine to jerk and misfire. In this case, you should inspect the spark plug, fuel injector, and the air/fuel mixture. You also want to replace all engine parts that may impede its performance.

5. Faulty Electrical System:

While electrical problems like wiring are less likely to cause the jerking while the AC is on, problems with the electrical power source may be responsible.  This power source includes issues with the battery and alternator.

These sources are the primary source of the engine and Ac system, causing the engine to struggle to stay on.

6. Damaged Serpentine Belt

A worn-out serpentine belt could cause your car’s jerk. The serpentine belt is responsible for driving the Ac compressor. A worn-out belt can cause slippage when the compressor is engaged, causing the car jumps when driving.

Symptoms of Bad Car Ac Compressor

I once change the entire motor mount, but my car keeps jerking when the Ac is on. I was disappointed to find out that the cause of the jolting was a bad compressor.

Here are symptoms to look for if you suspect your car’s Ac Compressor is bad. Remember that the Compressor should be one of the first components you inspect when your car jerks when the AC is on.

1. Jolting motion in the car

One obvious symptom of a bad car compressor is that the car jerks when the Ac is on. This vibration is because the bad compressor adds additional load on the engine, causing it to overwork.  A bad compressor finds it difficult to compress refrigerants, requiring the engine to work twice as hard to compress little.

2. Usual noise

When you turn on your air conditioner, you may hear squealing, clattering, or grinding noise. It is a sign your compressor is failing and needs to be changed urgently. The noise may be from worn-out bearings or components of the compressor.

3. Refrigerant leak

Check broken seals or valves around the compressor. Like all other components, the compressor is prone to wear and tear over time. The Freon leakage shows that you need to have your bad compressor replaced.

4.  Warm air

If you notice that your Ac is blowing hot air, then your compressor may have stopped working. The compressor compresses refrigerants, which remove heat from the cabin.

5. Bad Ac Compressor Clutch

The compressor clutch allows the compressor to engage or disengage from the engine power. If the clutch is stuck, Ac is stuck in one position and may overload the engine. The stuck clutch is responsible for reduced fuel efficiency.

All these symptoms let you know that something is wrong with your compressor, and you should seek professional help to replace it.

Can Spark Plugs Affect Air Conditioners?

The spark plug may indirectly affect your car’s air conditioning. The air conditioning system relies on the effective performance of the engine to fully perform. Also, the plug helps in igniting the air-fuel mixture.  If the plugs are faulty or worn out, the engine’s efficiency is compromised, especially under additional loads, like when the AC is on.

Does a Dirty Air Filter Cause Your Car to Jerk?

Yes, a dirty air filter may cause your car to jerk.  Remember, we previously said anything affecting the engine performance could cause the vehicle to jerk when Ac is on. The air filter helps to maintain the correct air-fuel mixture during the combustion. A clogged air filter will cause jolting and engine misfire.

How to fix car jumps when ac is on

Fixing a jolting car when your Ac is on will depend on the underlying cause. You will need the skills to diagnose the root cause and resolve it accordingly. Here are some of the common fixes to some of the common causes.

Fixing Car Jerks when Ac on YouTube
  1. Cleaning or replacing the Air filter: As identified above, the air filter may be responsible for the jerking.
  2. Cleaning or replacing the spark plugs: Defective spark plug can cause your car to misfire and overload the engine.
  3. Fix or replace the bad compressor with a good brand ac compressor.
  4. Inspect and replace the bad serpentine belt.
  5. Replace the damaged motor mount.
  6. Fix or replace vacuum leaks.
  7. Perform cooling system maintenance.
  8. Fix clutch issues in the car.


Your car jerking should always be addressed as it could be a sign of other underlying issues in the vehicle. We recommend frequent maintenance, including changing spark plugs and air filters to severe problems like replacing bad compressors. Regular maintenance is key to preemptively identifying potential issues and ensuring optimal performance.

Akindayini Temiloluwa

I am Akindayini Temiloluwa, an automotive expert writer and car enthusiast. I have over three years of experience in the automotive writing niche and have completed over 300 pieces of content from 50 projects. I have vast knowledge and skill in vehicle repairing, all mechanical work, car upgrades and maintenance. My goal as an automotive content writer is to simplify the most challenging concepts for my readers, help them self-diagnose what may be wrong with their vehicles and offer real value for their time.

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