The car shakes when it reaches 55 miles as I slow down the shaking stops

The car shakes when it reaches 55 miles as I slow down the shaking stops. What could be wrong with the car?

My car has 94000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi There,
Shaking at high speeds is often times related to tires that may be out of balance, low on air, potentially a badly aligned front end or failing suspension components or ball joints. When any of these things are not geometrically proper or aligned correctly, this causes an imbalance in the way the vehicle travels down the road and may cause the vehicle to vibrate or shake violently. This type of condition usually gets worse with more speed. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

How to Identify and Fix Common car Problems ?

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Tires are one of the most common causes of car vibrations. One of the possible issues are out-of-balance tires. Your problems may not be noticeable at slow speeds, but the shaking will intensify as you accelerate to 55-60 miles per hour. The steering wheel, or even the entire car, will start to vibrate.
The harder you brake, the more fluid pressure builds in the calipers, and the more pressure is applied to the brake pads and rotors. If the caliper or caliper pistons become stuck, it is unable to properly squeeze the brake pads against the rotors, which may cause you to feel some vibrations when you hit the brakes.
Any unusual shaking or vibrating forces coming from the engine is cause for concern. It could be something as simple as old spark plugs producing an uneven power delivery, it could be something serious like worn or broken engine mounts, or it could be even more serious in the case of internal engine damage.
The most prevalent cause of vibration is problems with your wheels or tires. The potential problems include improper wheel and tire balance, uneven tire wear, separated tire tread, out of round tires, damaged wheels and even loose lug nuts.
When your car vibrates every time you drive at 50-70 mph, it is most likely that your wheels are out of balance. The vibrations will emanate from the steering wheel across the seat and through the vehicle`s floor.
Worn or dirty spark plugs can cause a petrol car`s engine to misfire in one or more cylinders, which can cause vibrations when the car is idling or at running speeds. The easiest solution is to replace your spark plugs and check the related wiring. Engine vibrations can also be due to the air and fuel systems.
The most common cause of vehicle shakes at 50 mph or higher is tire balance. Again, transmission or drive lines can cause this, but the tires should be the first thing to have checked.
Is it something you should get looked at? The short answer is, Yes! A shaking or rocking sensation from your truck`s engine compartment, plus engine misfires is an indication that a problem is brewing. It may be as simple as replacing your spark plugs, but it also may be more involved than that.
The most common reasons a Ford Focus shakes when braking are bad brake rotors, bad brake pads, or a bad wheel bearing.
Tires. Tires are the most common reason a car shakes when it reaches 60 mph. Tire balance, or lack thereof, makes the steering shake as the car increases in speed. Typically, the shaking begins as an automobile gets to 55 mph and only becomes more problematic as the speedometer increases to 60 or more.
Unbalanced or Damaged Wheels – Around 45 MPH, you may feel a vibration through the steering wheel. As you increase in speed, the vibration will intensify. In order to rotate properly, the wheels of a vehicle need to be balanced.
The most likely cause of the shuddering most often happens in the vicinity of your car`s rims and tires. They plant your car to the road, and if anything is broken, will feel it. On a serious note, it may be a broken transmission mount or a broken caliper.
If you`ve noticed your car shaking when you apply the brakes, then there`s a good chance your brake rotors are out of round. If the problem is indeed with the brake rotors, then you will likely also feel a vibration in the brake pedal itself.
If vibration is felt at certain speeds, the tires may need to be balanced. If the tires are wearing unevenly and causing the car to vibrate, the driver may need a tire rotation. In some cases, the driver may need new tires to solve the problem of vibration.
While idle, the engine will complete about 10 revolutions or more per second. Because of its vast speed, the gauge displays the counts as multiples of 1,000. A vehicle that is operating normally should measure at about 1,000.
Low automatic transmission fluid can cause shaking. If the shaking is accompanied by the check engine light, it`s time to visit a mechanic. Drivers of manual cars might discover their clutch master cylinder is the source of the shaking.
Typically it`s from a damaged inner CV joint. These are located on the end of each axle. They both have an inner and outer joint that could be damaged and shake when you press the gas pedal. Another cause could be a broken motor mount.
There are a few reasons your car may shake when accelerating but not coasting. The most common reason is that the engine is misfiring. When the engine misfires, it doesn`t run as smoothly as it should and can cause the car to shake. Another possible reason is that the spark plugs or ignition coils are dirty or damaged.
“Clicking” Noises When Turning

Though it`s sometimes described as a loud click and sometimes described as a pop, this noise is unmistakable once you hear it. It presents itself when you turn the vehicle, and it`s due to the loose joints of a worn CV axle.

Vibration can be caused by one or more factors at any given time, the most common being imbalance, misalignment, wear and looseness. Imbalance – A “heavy spot” in a rotating component will cause vibration when the unbalanced weight rotates around the machine`s axis, creating a centrifugal force.
In many vehicles a common cause of engine vibration is worn out or faulty sparkplugs. Worn out or dirty sparkplugs will cause the car`s engine to misfire or not properly fire on each and every cylinder. When this occurs, it is commonly referred to as the engine missing or not firing on all cylinders.
What Causes A Ford To Shake? We`ve gone over four different issues that could cause your vehicle to shake on the move. Spark plugs, joint issues, motor mounts, and wheel attachment troubles are the most common reasons for this trouble. However, some of these items are more common than others.
A: A four-cylinder engine will typically have a slight vibration when idling. This is inherent in the design and may in fact be normal.
If you begin to feel persistent shaking in your car, it`s best that you get to the problem right away before continuing to drive. Continuing to drive with the shaking can result in further damaging parts, ruining your tires, and other costly problems that could be avoided by a quick trip to your mechanic.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

The car shakes when it reaches 55 miles as I slow down the shaking stops
ANSWER : Hi There,
Shaking at high speeds is often times related to tires that may be out of balance, low on air, potentially a badly aligned front end or failing suspension components or ball joints. When any of these things are not geometrically proper or aligned correctly, this causes an imbalance in the way the vehicle travels down the road and may cause the vehicle to vibrate or shake violently. This type of condition usually gets worse with more speed. I would recommend having a professional from YourMechanic come to your location to diagnose and inspect your vehicle.

Rough idle and shakes at stops
ANSWER : What you are describing sounds like a dirty or failing idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

I was stopped on the freeway, started to go about 5 mph, the car jerked and stop without warning like the wheels locked up.
ANSWER : Hi, thanks for writing in. I’d be happy to try to help. It is hard to definitively diagnose what the issue is. At first it seems like a transmission issue. Automatic transmissions are rather complicated and can do strange things when they malfunction. If not an issue with the transmission, you could also have a clutch issue. Always start by checking the simple components first. Check your transmission fluid level. Make sure your transmission filter is clean and debris free. When you have the transmission pan off, you can look and see if there are any metal shavings at the bottom. There is often a small magnet at the bottom of the pan designed to gather any metal shavings for a quick diagnosis. This is a sign of more serious transmission problems. Unless you have experience with automatic transmissions, it is not recommended that major repairs be done at home. I suggest taking your car to a transmission specialist for help.

Car starts, shakes then Dies out within seconds!
ANSWER : Hi there. The dreaded rotten egg smell is caused by either a clutch that is damaged or the catalytic converter that needs to be replaced. I would recommend before you take your car to any repair facility or attempt any repairs; first have a professional mechanic come to your location and complete a car starts then dies inspection. This will allow them to pinpoint the source of your issues and recommend the right repairs.

Whenever I drive 1.5 miles, the s3 light starts blinking and then when I stop my car and come back to it, the car won’t start.
ANSWER : Hello, thank you for writing in. It is difficult to determine the issue without some more information. To start, when the check engine light illuminates, you want to scan the vehicle for diagnostic codes. These are what set the check engine light off, and are meant to tell the driver what the computer has detected is wrong. Codes can be pulled at most automotive parts stores, and by most technicians. Once you have that information you can focus in on one component or system. If the engine is truly overheating, then you want to start by checking your coolant and fluid levels. For more help with diagnosing and resolving the issue, contact our service department to schedule an appointment.

When I stop at the stop light or a stop sign my car shuts off.
ANSWER : It sounds like you may have a dirty or failing idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. This is also an important function when starting the motor as it allows the motor to run and idle on it’s own once the motor fires. When you accelerate, the engine RPM increases, and as you let off the gas, the RPM slowly returns to the normal idling speed with the help of the idle air control valve making the transition from a higher RPM back down to idle speed while adjusting the air/fuel ratio constantly to allow this to happen smoothly. When the engine RPM drops below the normal range of about ~800 RPM, this often times will cause the engine to stall indicating a dirty or faulty idle air control valve. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your vehicle.

car shakes when idle and accelerating
ANSWER : It is very possible that you have a valve cover gasket or spark plug tube seal leak on your vehicle. These type of leaks will allow oil to leak onto the spark plugs causing misfires. When the engine misfires due to oil getting on the spark plug, the engine oil will burn. Since oil and tires are both petroleum products, they will both smell similar when they are burning. I would recommend having an oil leak inspection performed by a qualified professional to determine if there is an oil leak. Consider YourMechanic as an Oil/Fluid leak inspection can be peformed at your home or office.

Eps light came on and car started to slow down, stepped on gas and car was still slowing down. Had to shut it off then turn it on
ANSWER : Hi there. In most cases when the EPS light comes on, it indicates an electrical fault with the electronic power steering system. As a safety device, most of the time, Hyundai and other manufacturers will activate a fail safe or "limp mode" that restricts the throttle to ensure you have an opportunity to drive safely to a mechanic to have this issue inspection. I would recommend having a professional mobile mechanic come to your location to complete a service light inspection, so they can determine what’s going on with your Hyundai.