What is the cause of Mercedes Benz C class abnormal noise? What are the causes of abnormal noise in

The solution to the squeak needs to be the right medicine, the scope of what you said is too broad, and if you want to solve the problem, you still need to describe the problem carefully.

Mercedes-Benz C-Class ( Price |What are the causes of abnormal engine noise? Squeak and squeak are related to engine speed, load, temperature, duty cycle, etc.

1. The relationship between abnormal noise and engine speed.

The presence of most common squeaks and squeaks in an engine depends on the state of the engine's rpm.

1. Abnormal noise only exists when it is running at idle speed or low speed. The reasons for the sound are: the gap between the piston and the cylinder wall is too large; The piston pin assembly is too tight or the connecting rod bearing is assembled too tightly; The gap between the tappet and its guide hole is too large; The air-flow cam profile is orange and wearable; Sometimes, the starter grip comes loose and the pulley makes a sound (noticeable when the speed changes).

2. The sound is disordered when maintaining a certain speed, and a short sound is made successively when decelerating sharply. The reasons for the sound are: the camshaft timing gear is cracked or its fixing nut is loose; The curved school broke the shaft; The piston pin bushing is loose; The axial clearance of the camshaft is too large or its bushing is loose.

3. The abnormal sound occurs when the engine accelerates sharply, and the sound still exists when maintaining high-speed operation. The reasons for the sound are: the connecting rod bearing is loose, the bearing is burned or the size does not match and rotates; loose crankshaft bearing or bearing burning capacity; The piston pin is broken; The crankshaft is broken.

Second, the relationship between abnormal noise and load.

There is an obvious relationship between a lot of abnormal noise on the engine and its load, and the method of relieving the load can be taken cylinder-by-cylinder during diagnosis, and the load of one or two cylinders is usually relieved by the single-cylinder or double-cylinder fire breaking method to identify the relationship between the abnormal noise and the load.

1. A cylinder is fired, and the abnormal noise is absent or reduced. The reasons for the sound are: piston knocking on the cylinder; Loose connecting rod bearings; piston ring leakage; The piston pin is broken and broken.

2. If a cylinder is fired, the sound will be aggravated, or there will be no sound at this time. The reasons for the sound are: the piston pin copper sleeve is loose; The piston skirt cone is too large; piston pin out; The connecting rod bearing cover fixing bolt is too loose or even the connecting rod bearing alloy is burned and melted off; The flywheel retaining bolts are too loose.

3. The abnormal sound of the adjacent two cylinders is reduced or disappeared. The reason for the sound is that the crankshaft bearing is loose.

3. The relationship between abnormal noise and temperature.

1. The sound is low temperature, and the sound is reduced or even disappeared when the temperature rises. The reasons for the sound are: the gap between the piston and the cylinder wall is too large; The piston is misaligned due to the depth and width of the main bearing oil groove; Low oil pressure and poor lubrication.

2. There is a sound after the temperature rises, and the sound decreases or disappears when the temperature decreases. The causes of the ringing are: premature ignition caused by overheating; The long and minor axes of the piston skirt oval are opposite; The piston ovality is small, and the gap between the piston and the cylinder wall is too small; piston deformation; The gaps between the piston rings are too small.

Photo by Shi Lili) @2019

The reason for the sound from the Mercedes-Benz C-Class console is that the plastic mold has deviated or the side cover installation has changed, and the bumps cause the sound of rubbing and squeezing against each other. Find the location of the sound to confirm the friction point, then fill it with a rubber pad.

It has a good cushioning effect; If not, just find some Mercedes Benz inner tubes to make, and if it's due to looseness, first tighten them to make rubber pads.

Class C cars first listen and observe while driving slowly, taking care to determine the location of the abnormal sound and see if any foreign objects (e.g. thin rail cables) have been accidentally inserted into the toolbox, if there are any foreign objects in the gaps of the ** controller, and if there are foreign objects around.

If sound remains after cleaning, if most parts of the controller are used frequently, if individual parts are loose or not installed in place during retrofitting, etc., there is debris such as baffles or septa.

Millions of car purchase subsidies.

Mercedes C-Class (solution).

When the vehicle is used for a certain period of time, the abnormal sound of the Mercedes-Benz C-class door is a problem that owners will encounter. The following summarizes several causes and solutions for abnormal door noises for the reference of owners of car tremor cracks, hoping to help Mercedes-Benz owners in daily use.

1. The hinge is jerky and produces abnormal noise.

Because the door is often opened and closed, and the force and amplitude of each person's operation are different, the wear and tear of the C-class door hinge chain is great, and over time, the door will not be closed tightly, resulting in abnormal noise.

Solution: The abnormal sound caused by the Hinge of the C-class door is similar to the abnormal sound of the door of your own house, and the same way to solve the abnormal sound of the hinge is to add lubrication.

Always keep the door hinges lubricated to reduce wear and prevent corrosion. To use Mercedes-Benz 4S shop maintenance special grease,. It is not advisable to use engine oil or ordinary butter, it will freeze in winter, and the harmful smell will affect your health.

2. The aging of the sealing strip produces abnormal noise.

There is a rubber seal around the door to prevent wind and rain from entering the cabin. However, once the sealing strip is damaged due to aging, it will cause water leakage in the cabin, which will increase the wind noise and other abnormal noises during driving.

Solution: Since the gaps between the seals are easily stuffed with sand, the sand should be cleaned frequently with a brush. This is followed by a highly penetrating protective agent to prevent the weatherstrip from aging.

If the seal is severely damaged or deteriorated, it is best to replace it with a new one.

3. Abnormal noise caused by elevator failure.

The glass vibrates and makes abnormal noises, which may be due to the lack of lubrication of the lift or the loose screws of the glass regulator.

Solution: If the fixing screw of the lifter is loose, the installation position of the guide rail is deviated or the glass lifter is damaged, the maintenance method is to clean and replace the glass mud groove or loosen the glass installation screw, adjust the position of the glass, and tighten the lifter screws. The noise is mostly due to the lack of lubrication and maintenance of the glass regulator and ant ridge inside the door, and the grease of the door accessories should be used, and it is recommended to use a 4S special brand, such as Tiger Head Hotolube or Kruber, the lubrication effect is obvious and durable;

Summary: In fact, in the final analysis, to avoid the abnormal noise of Mercedes-Benz C-class doors and other interiors to the greatest extent, the key is to develop good car habits, slow down when walking on bad roads, and remember not to drive too violently when the road conditions are good, so as to keep the car in good condition.

Mercedes C-Class (solution).

When the vehicle has been used for a certain period of time, the abnormal noise of the Mercedes-Benz C-class door is a problem that car owners will encounter. The following summarizes several causes and solutions for abnormal door noises for the owner's reference, hoping to help Mercedes-Benz owners in daily use.

1。The hinges are rough and produce abnormal noises.

Because the door is often opened and closed, and the strength and amplitude of each person's operation are different, the Hinge of Class C door is worn greatly, and the door will not be closed tightly over time, resulting in abnormal noise.

Solution: Class C The abnormal noise produced by the door hinges is similar to the abnormal noise produced by your own door. Similarly, the solution to hinge squeak is to add lubrication.

In general, you should always keep your door hinges lubricated to reduce wear and prevent corrosion. Use special grease to maintain the Mercedes-Benz 4S shop. It is not advisable to use engine oil or ordinary butter, as it will freeze in winter and the harmful smell will affect your health.

2。The sealing strip is aging and has abnormal noise.

Rubber seals around the doors prevent wind and rain from entering the cabin. However, once the sealing strip is aged and damaged, it will cause water leakage in the cabin and increase the abnormal noise such as wind noise during driving.

Solution: Since the gap between the sealing strips can easily fill with dust, dust should be cleaned frequently with a brush. Then, a protective agent with high permeability is applied to prevent the sealing strip from aging. If the seal is badly damaged or aged, it is best to replace it with a new one.

3。Abnormal noise caused by elevator failure.

The abnormal noise caused by glass vibration may be caused by insufficient lubrication of the regulator or loose screws of the glass regulator.

Solution: The set screw of the lifter is loose, the installation position of the guide rail is offset, or the glass lifter is damaged. The repair method is to clean and replace the glass trough or loosen the glass mounting screws, adjust the position of the glass, and tighten the lifting screws.

The abnormal noise is mostly due to the lack of lubrication and maintenance of the window regulator in the door, and the grease of the door accessories should be used. It is recommended to use 4S special brands, such as Tiger Head brand Hotolube or Kruber, the lubrication effect is obvious and long-lasting;

Summary: In fact, in the final analysis, the key is to avoid abnormal interior noises such as Mercedes-Benz C-class doors to the greatest extent and develop good car habits. If you don't take a good road, slow down, and remember not to drive too hard when the road is good, so that the car is always in good condition.