The A6 throttle sounds louder.

There are the following solutions for excessive engine sound:

1. Drive on the expressway for a period of time while ensuring safety.

Often driving at a low speed and stopping on urban roads for a long time, the engine is not fully released, which is prone to carbon deposition and leads to greater noise. So if you often drive in the city, you should take time out to run the highway.

2. Maintain the engine.

When you refuel, you can add something from fuel treasure, which can effectively remove carbon deposits. After all, the oil products in our country need to be improved, so it is necessary to maintain the engine properly.

3. Change the oil.

It is necessary to maintain the car regularly and on time. Even if the mileage is not reached, the old engine oil should be drained, because the engine oil will be oxidized. After a long time, its indexes will decline, which will not protect the engine well and produce noise. So change the oil in time.

4. Clean the throttle.

If the throttle valve is opened for a long time, it will hide dirt and shelter evil people, so the engine noise is really too loud, probably because the throttle valve is dirty. It will be much better after cleaning in a professional repair shop.

5, do sound insulation.

The noise may also be caused by the poor sound insulation performance of our car. Due to the aging of various sound insulation protection, the originally inaudible sound is introduced into the car, so doing sound insulation can also reduce noise.

Extended data:

Working principle of internal combustion engine

Working process: air intake-compression-fuel injection-combustion-expansion work-exhaust.

1, intake stroke

The working medium entering the cylinder is pure air. Due to the small resistance of the intake system of diesel engine, the intake terminal pressure PA = (0.85 ~ 0.95) P0, which is higher than that of gasoline engine. The final intake temperature ta = 300 ~ 340 k, which is lower than that of gasoline engine.

2. Compression stroke

Because the compressed working medium is pure air, the compression ratio of diesel engine is higher than that of gasoline engine (generally ε = 16 ~ 22). The compression end point pressure is 3000 ~ 5000 kPa, and the compression end point temperature is 750 ~ 1000 K, which greatly exceeds the auto-ignition temperature of diesel oil (about 520K).

3. Power stroke

When the compression stroke draws to a close, diesel oil is injected into the cylinder combustion chamber at a high pressure of about 10MPa under the action of a high-pressure oil pump, and it is ignited immediately after being mixed with air in a short time. The gas pressure in the cylinder rises rapidly, with a maximum of 5000 ~ 9000 kPa and a maximum temperature of1800 ~ 2000 K. Because a diesel engine ignites itself by compression, it is called a compression ignition engine.

4. Exhaust stroke

The exhaust of diesel engine is basically the same as that of gasoline engine, but the exhaust temperature is lower than that of gasoline engine. Generally, TR = 700 ~ 900 K. For a single-cylinder engine, its speed is uneven, the engine works unsteadily and vibrates greatly. This is because only one of the four strokes does work, and the other three strokes consume power to prepare for work.

The flywheel must have enough moment of inertia, which will lead to the increase of the mass and size of the whole engine. Using multi-cylinder engine can make up for the above shortcomings. Modern cars mostly use four-cylinder, six-cylinder and eight-cylinder engines.

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