Engine Vibration can be quite normal when your vehicle is running. Vibrations may be caused by the movement of the crankshaft, transmission gears, and other critical components within the car engine. However, in some situations, engine vibrations may exceed normal levels. In this article we will dig deeper into the possible causes of engine vibration and what should be done about it.
Engine Vibration Causes
- Weakened spark
A faulty or fouled spark plug, bad ignition cables, or worn coils may all contribute to a poor spark. A misfire may be caused by a faulty spark in one or more of your cylinders. Since the cylinders are firing unevenly, the engine can run rough as a result of the misfire.
Excessive engine vibration can be caused by a variety of factors. To find the source of the problem, you'll have to trace the engine's ignition system down the line. Check the spark plugs to see if they're worn and need to be replaced, or if they only need to be washed and gapped.
A multimeter should be used to check the resistance of the ignition cables to ensure that they are within requirements. The ignition coils would also need to be tested to see if their resistance is within the manufacturer's requirements.
By getting your car tuned up according to the manufacturer's recommendations and testing the above points in the ignition system, you will reduce excessive engine vibration caused by a faulty spark.
Timing Belt Issues
Another common cause of engine vibration in cars is a problem with the vehicle's timing belt or other belt-driven accessories. Timing belts and other belts that are loose or broken can cause fans and other components powered by belts to not rotate or turn at a consistent speed, resulting in unusual sounds and vibrations from your car's engine.
To prevent these issues, you can check all of the belts in your vehicle on a regular basis to ensure that they are free of cracks and ribbing, and that they are tight and running properly.
- Clogged injectors
Injectors supply fuel to the engine by spraying it into the combustion chamber via a port. When debris in the system obstructs the spray, it can result in a misfire, which causes the cylinders to fire unevenly, resulting in excessive engine vibration.
Check for a bad fuel injector by replacing injectors with different cylinders and seeing if the misfire switches accordingly. You can reduce or avoid this by changing your fuel filter on a regular basis, according to the manufacturer's recommendations.
- Engine mounts that have been worn out
Engine mounts secure the engine to the chassis/frame of the vehicle. They're also made to reduce the amount of engine vibration that gets into the vehicle. When engine mounts wear out, it's normally the rubber or liquid sections that have worn out, and increased vibration is one of the symptoms.
You can verify this by placing the car on a lift and looking at the engine mounts. If you notice a rise in engine vibration coming through to your points of contact with the vehicle, such as your seat, steering wheel, or shift knob, get your engine mounts tested.
- Hoses that are loose or disconnected
Many forms of engine vibration may be caused by loose or disconnected hoses. A loose or disconnected air hose or vacuum hose in your car's engine can cause a lot of shaking and vibration. Simply look for any loose or disconnected hoses and reattach or repair them as required to fix the issue..
- Exhaust system leak
The sound of igniting fuel within the cylinders is muted by the exhaust system of a vehicle. Each ignition is similar to an explosion, and in an internal combustion engine, some of these explosions occur simultaneously while the engine is running. The mufflers in the exhaust system are in charge of suppressing the explosions caused by the ignited gasoline.
If the pipes or mufflers are worn or damaged, they will no longer be able to do their job, and you will hear more noise from your engine. Vibrations from your engine and exhaust system will echo into your car due to noise from a worn exhaust system. To avoid this, inspect the car's exhaust system for leaks in the pipes and mufflers, as well as rattles in the mufflers, when it's up on the lift for service.
- Fuel Intake System Faulty or Improperly Adjusted
An improperly adjusted fuel intake system is another common cause of engine vibration and unpleasant shaking. Idling issues that trigger engine vibration may often be as easy as changing the idle on a carburetor or cleaning components in the fuel intake system to allow more fuel to move through the engine, resulting in cleaner and more powerful combustion in your car's engine.
- Wheel Issues
The wheel is one of the most common causes of engine vibration. If you feel like the vibration is coming straight from the steering wheel, it may be a misaligned wheel or worn out wheel bearings. Another factor may be warped ball joints, which generate grating vibration at high speeds.
- Tire Issues
It's the most popular of all the causes, as tires account for nearly 80% of all car vibrations. Tire balance, tire rotation, or tire replacement may all help to reduce vibrations.
- Extreme Weather Conditions
It is very typical for cars to shake in cold weather. When it's cold outside, the engine vibrates more than normal. If the problem resolves on its own when the car is driven in normal weather, no additional steps are needed. Since the engine can't run at its best in cold weather, vibration increases.
- Car Axle
Sometimes, it seems that the cause of engine shaking is the engine itself, when in fact, it is the axles that need to be addressed. Even if there are no visible signs of injury, the car's axles may be damaged in a crash. So, if you're feeling increased vibration right after a crash, you must consult a mechanic.
- The Crankshaft Damper
Vibrations in your car can be caused by engine problems. The crankshaft damper might be a factor to consider when diagnosing engine vibration triggers if you feel the engine shaking. This component's primary function is to reduce vibration.
It is more widely used in diesel engines. Your engine will shake even more if there's a risk it's defective or has completely stopped running. When you have a problem like this, you should call a mechanic.
Engine Vibration at Idle (Diesel)
In comparison to gasoline engines, diesel engines idle at low RPMs. The more slowly an engine turns, the more apparent the shaking becomes, similar to how the Earth spins so quickly that we don't notice it. We would note if the Earth slowed down in speed, just like a diesel engine versus gasoline. Also, since many diesel engines are huge, the vast quantities of weight shifting gradually becomes evident.
Engine vibration when accelerating
If the inner CV (constant-velocity) joint is weakened or failing, the car can vibrate under heavy acceleration. Mild movements can become violent shaking as they worsen under load. The most common cause of CV joint damage is a tear in the joint boot. And the only solution is to completely replace the CV joint.
Other reasons include broken motor mounts. When the engine is idling, you will be able to feel a faulty motor mount, but the shaking will become more noticeable as the engine works harder when accelerating. If a bad motor mount is replaced, the vibrations should improve. Keep in mind that if one of the motor mounts fails, the other mounts will have to take on more of the load and are more likely to fail as well.
Unbalanced tires could also cause engine vibration. When tires are rotating any weight imbalance, no matter how slight, will turn to small vibration. The shaking will be more apparent at higher speeds, as the tire is spinning even faster, and the steering wheel will actually shake. You can have an unbalanced tire if your car vibrates at a steady speed and becomes worse at higher speeds.
Also check the lug nuts on your wheels. If they weren’t torqued down on the hub properly, it will eventually get loose over time. If that happens the wheel would slightly wobble and that will translate to your car shaking. The lugs could loosen all the way out if left untightened, and your wheel could fall off while you're driving. You don't want that to happen.
Also if the brake caliper on a wheel becomes faulty it will cause it to stick causing car vibrations. The steering wheel will vibrate in this situation as you approach 40-50 miles per hour. If you accelerate at higher speeds, the vibrations can become more intense. You'll probably detect a burning odor coming from the car as you come to a stop.
If you suspect a stuck brake caliper, you should be able to use your nose to determine which wheel it is at based on the smell. Parts of the brake system should be examined, with special attention (caliper bolts, slides, and piston). Cleaning and re-lubricating the parts can help in some cases, but failed brake components will need replacement.
Engine Vibration When Aircon is On
When the air conditioner is switched on, most people complain that their engine vibrates. There may be a variety of explanations why this occurs in your vehicle. You don't need to be concerned because it can happen at any time and in any place.
However, it is preferable that you understand the causes of this predicament so that the mechanics cannot take advantage of you. Here are some common causes of engine vibration when you switch on the air conditioner.
- Engine Load
The AC compressor puts a strain on the engine, and when the load exceeds a certain point, vibration occurs. If the load continues to increase, some engine components will eventually wear out. Other causes may involve a problem with a cooling fan or a blockage in the air conditioning system. Take your car to the nearest AC technician as soon as possible if you find yourself in this situation.
- Engine Mountings/Foundation
The engine and suspension are held in place by the engine mountings. Each mount has a specific function in maintaining a proper suspension angle by holding the transmission and engine in place. The mountings are under a lot of strain.
When the air conditioner is turned on, the mountings are subjected to additional stress due to the high starting load. As a consequence, any problem with the mounts can cause vibrations or shakes. As the AC compressor puts pressure on the engine, the broken mount can cause increased vibration and noise. As a result, double-check your mounts to solve the problem. The mounting can appear to be in good condition, but it is actually worn out or cracked.
- Throttle Position Sensor Failure
Since a bad TP sensor can't regulate the RPMs, when the AC is switched on, the RPMs don't stay steady, causing the car to shake and the RPMs to be unstable. To fix the problem, the sensor must be cleaned or replaced.
- AC compressor
A defective AC compressor may also be causing vibrations when the air conditioner is turned on. A simple observation is the most accurate technique for detecting this problem. If you notice a difference in your car's pick when the AC is on versus off, your compressor needs to be replaced. You can also search by running your hand over it. When you turn on the air conditioner, this sort of compressor puts out more load than normal, resulting in massive vibrations.
There are many common causes of engine vibration in a vehicle, all of which result in shakiness and noises that are not only annoying but can also be disturbing and frightening. However, regardless of its age, there are ways to make your powertrain feel fresh and run smoothly again. But first you must know what the most common causes of engine vibration are. Hope this article helps in preventing unnecessary stress and worry, and helps you know how to explain the issue and symptoms to a car mechanic when it's time to fix it.