When it rattles and knocks - What causes vibrations in the car
Driving a car is especially pleasant when it is carried out with maximum comfort. Smooth glide at any speed, pleasant music and no outside noise - that's how nice it is to drive your own car. But if it rattles, shakes and vibrates, then driving pleasure quickly turns into a real stress. In addition, a vibrating vehicle can also quickly lead to collateral damage and lead to dangerous driving situations. That is why you should always explore even the weakest vibrations. In most cases, the situation only gets worse.
Many causes, one symptom
A vibrating car is a rather non-specific diagnosis. . There are several possible causes for this symptom. Typical causes of vehicle vibration are:
– track geometry
– chassis
- engine
- exhaust system
– tires
- cardan shaft
Therefore, it is necessary to more precisely determine the reasons for the change in driving experience. This is done systematically.
| 1. At what speed do vibrations occur? 2. Vibrations also occur when the car is turned off but rolling? 3. Do vibrations also occur when the car is stopped with the engine running? 4. Vibrations occur only when braking? |
1. Vibrations in the car, depending on the speed.
If vibrations occur only at high speeds, this is usually due to tires or counterweights . They may come off the rim. After that, the wheel no longer spins "in a circle". To fix the problem, visit your nearest workshop and have the wheel balanced.
Even if the damage can be repaired quickly and inexpensively, it should not be delayed too long. Wheel vibration affects the entire steering mechanism . Tie rod ends, stabilizers and wishbones may also suffer.
 If any steering gear is damaged, the car will vibrate even at low speeds . Even on speed 20 km/h there is a "soft" driving feel that gets worse and worse at higher speeds. it occurs, for example, when hitting a curb at a right angle. Then the wishbones usually bend a little and the ball joint fails. Then both must be replaced. |
| Similar symptoms occur when the shock absorbers fail. . The car then bounces too much, making it difficult to keep track. If the car is crooked, the springs are broken. In this case, too, the machine does not bounce properly and starts to vibrate. |
| Old and defective tires can also cause vibration. . If the tire has a "brake plate" or the carcass is cracked on the side, it will begin to vibrate while driving. This damage should also be repaired immediately, as the tire can burst at any time. |
| If the axle boot is damaged and grease has leaked out , the wheel bearing will become very hot. It can also become noticeable due to vibrations while driving. It's pretty easy to spot: the wheels are turned all the way out, and you can look behind the steering wheel. If everything is covered in black grease, you know where the vibrations are coming from. .Only the way out is to disassemble everything and replace the anther and wheel bearing. However, be aware that axle boot can be damaged by aging or marten bite. In both cases all other rubber parts such as hoses, sleeves and insulation should be checked. In most cases, you will find another damaged part. |
The cause of vibrations from the wheels has yet to be identified: If the wheel bolts are loose or starting to loosen, they will show this with a strong vibration in the wheel area. . This is a serious build error, and it should be quickly corrected with a cross. All wheels must also be tightened with a torque wrench at the nearest specialist workshop.However, the wheels do not loosen just like that. . If they were properly mounted before then it is very likely that there is an outside influence. In this case, you must report to the police. |
2. Vibrations when driving
If the car vibrates when the engine is off, then the problem can be reduced to the suspension , steering gear or tires .
3. Vibrations when the car is stopped but turned on
If the vibrations are coming from the engine, this may be due to the following reasons:
- Faulty engine mount
- one or more cylinders do not work
- clogged fuel filter
- defective dual mass flywheel
| If the engine mount is loose or even broken , this means that the motor is not correctly attached to its damping elements. Then it starts to wander and causes a rumble and shaking on the body. |
| A faulty spark plug or loose ignition cable may be enough to cause one cylinder to fail. . Then the cylinder only "pulls" the rest. This gives the engine a slight imbalance, which can become especially noticeable when the car is stationary. However, it is best to recognize this fault while driving:the car loses a lot of power and no longer accelerates as usual. |
| The same thing happens if the fuel filter is clogged. . It only passes gasoline or diesel unevenly, which means that the engine is no longer supplied with fuel evenly. It can also lead to vibrations and loss of power. |
| The dual mass flywheel is part of the clutch. . It's a massive rotating component needed for smooth shifting. However, it is permanently lubricated and therefore has a limited service life. When the lubricant is used up after 150 km run, its action becomes the opposite: instead of ensuring a smooth ride, it rumbles more and more, vibrates and knocks. The only way out is to replace it, but it is quite expensive. Such a fault can be narrowed down even further: if it rattles when shifting gears, it is usually the dual mass flywheel. To prevent this fault, it is recommended to replace the dual mass flywheel as a precaution when repairing the clutch. Even if the dual-mass flywheel still has a remaining service life of 20 000 kilometers It's usually not worth waiting that long. If everything is already disassembled, you should invest about 250 euro and save on subsequent repair costs. |
| On the other hand, it's even cheaper if the vibrations come from the exhaust system: if the retaining rubber is lost, the exhaust can hit the bottom . Depending on how fast or how often this happens, it may feel like a vibration. |
| The same thing happens if the screws on the manifold are loose . This is very rare, but sometimes it happens. Such faults can usually be corrected in a few simple steps. |
4. Vibrations in the car when braking
If there is a strong vibration when braking, then usually this has only one reason: the brake disc has become wavy . This occurs when the discs overheat, the brake pistons seize, or poor quality material is used on the disc or pads.
Conclusion: Good diagnostics, safe driving
Identifying the cause of vibrations in a car makes it easier to find and fix the faulty part. Whether you want to repair the damage yourself or have it repaired by a workshop: by accurately describing the symptoms, the search for the cause becomes much faster.
