Why Your Car Shakes When the AC’s On: Engine Mounts to Check

Do you ever wonder why your car starts shaking when you turn on the AC? It’s like your vehicle suddenly caught a case of the jitters, right? Picture this: you’re cruising down the road, ready to enjoy a cool breeze, but instead, you get a shaky surprise. Fret not, as we’re here to unravel this mystery for you.

Common Reasons for Car Shaking When AC is Turned On

If you’re wondering why your car shakes when you turn on the AC, there are several common reasons behind this issue. Understanding these reasons can help you address the problem effectively.

  • Engine Misfire: When the engine misfires, it can cause your car to shake. This can be due to issues with spark plugs, fuel injectors, or the air-fuel ratio.
  • Worn Engine Mounts: Engine mounts are designed to absorb vibrations, but over time, they can wear out. When this happens, the engine vibrations can be felt more strongly, especially when the AC is on.
  • AC Compressor Issues: Problems with the AC compressor, such as a faulty clutch or low refrigerant levels, can lead to shaking when the AC is activated.
  • Low Refrigerant Levels: Insufficient refrigerant in the AC system can also cause the compressor to work harder, resulting in vibrations in the car.
  • Imbalanced AC Components: If the AC system is out of balance or certain components are worn out, it can put additional strain on the engine, leading to vibrations.

Keep these common reasons in mind when addressing the issue of your car shaking when you turn on the AC. Check for these factors to pinpoint the root cause and seek professional assistance if needed.

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Low Refrigerant Level

If your car is shaking when you turn on the AC, a Low Refrigerant Level could be to blame. When there isn’t enough refrigerant flowing through the AC system, it can lead to improper pressure levels. This, in turn, might cause the system to work harder, leading to vibrations in your vehicle.

To address this issue, you can schedule a professional inspection to check the refrigerant levels in your car’s AC system. Recharging the refrigerant to the proper levels can often resolve the shaking problem and improve overall AC performance.

Remember, maintaining the optimal refrigerant level in your car is crucial for the AC system to function efficiently and keep you comfortable on the road.

Refrigerant Levels Recommendation
Low refrigerant levels may cause vibrations in the car when the AC is on. Schedule an inspection to check and recharge the refrigerant in your AC system.

Engine Misfires

When the Engine Misfires, it can cause your car to shake when you turn on the AC:

  • An engine misfire means one or more cylinders fail to ignite properly, leading to a lack of power and rough running.
  • This can result in vibrations being felt throughout the vehicle, particularly when the additional load of the AC is activated.
  • Misfires may be caused by issues such as faulty spark plugs, a clogged fuel injector, or a vacuum leak.
  • To address engine misfires, have your vehicle inspected by a mechanic who can diagnose and resolve the underlying problem.
Fact Data
Consequence Vibrations in vehicle
Typical Causes Faulty spark plugs, clogged fuel injector, vacuum leak
Resolution Professional inspection and repair

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Worn Out Engine Mounts

If your car shakes when you turn on the AC, worn out engine mounts could be the culprit. Engine mounts are responsible for holding the engine in place and absorbing vibrations. Over time, these mounts can wear out or break, leading to excessive engine movement and causing your car to shake noticeably.

Signs of Worn Out Engine Mounts

  • Excessive vibration when you turn on the AC
  • Loud clunking noises when you accelerate or decelerate
  • Visible wear or damage on the mounts

Impact on Your Vehicle

  • Increased vibrations throughout your car
  • Transmission misalignment and potential damage
  • Reduced driving comfort and stability
  1. Inspect the engine mounts for any visible signs of wear or damage.
  2. Consult a professional mechanic for a thorough inspection and replacement if necessary.

Always prioritize your safety and the maintenance of your vehicle for a smoother and safer driving experience.

Checking and Fixing the Issue

If your car shakes when you turn on the AC, it’s crucial to address this issue promptly. Here’s how to check and fix the problem:

  • Visually inspect your engine mounts for any signs of wear, damage, or shifting. Look for cracks, tears, or separation from the mounting brackets.
  • Test the engine movement by having a friend turn the AC on and off while you watch the engine from the side. Excessive movement indicates worn mounts.
  • Seek professional assistance if you notice visible damage or significant engine movement. A mechanic can provide a thorough assessment and recommend the necessary repairs.
  • Replace worn engine mounts to restore stability and reduce vibrations. This simple fix can greatly improve your driving experience when using the AC.

Remember, addressing worn engine mounts can not only reduce shaking when the AC is on but also prevent long-term damage to other components. Keep an eye out for these signs and take action promptly for a smoother and safer ride.

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Ensuring your vehicle’s engine mounts are in good condition is crucial for minimizing vibrations, especially when the AC is running. By visually inspecting and testing the mounts, you can identify any issues early on and prevent further damage. Replacing worn engine mounts not only restores stability but also enhances your driving experience. Taking care of this matter promptly will not only reduce shaking with the AC on but also safeguard other components from potential long-term harm, guaranteeing a smoother and safer journey.

Frequently Asked Questions

What are engine mounts, and why are they important in a vehicle?

Engine mounts are components that support the engine and keep it secure within the vehicle. They help reduce vibrations and absorb road or engine noise, ensuring a smoother driving experience.

How can I check if my engine mounts are worn out?

Visually inspect the engine mounts for visible wear, cracks, or shifting. You can also test engine movement by gently revving the engine while observing for excessive motion.

Why is it crucial to address worn engine mounts promptly?

Worn engine mounts can lead to increased vibrations, especially when the AC is activated. Prompt replacement is necessary to restore stability, prevent further damage, and ensure a safer and more comfortable driving experience.

Charlie Thomson is Appliance Mastery's expert on laundry appliances. With a degree in mechanical engineering and over 8 years of experience in the appliance repair industry, Charlie is a go-to resource for homeowners who want to tackle common issues with their washing machines, dryers, and dishwashers.

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