How to reduce engine noise

The engine itself will not reduce the noise. Fuel is often used to reduce knocking. Adding soundproof cotton will have a little noise reduction effect. In addition, the following measures can be taken to reduce engine noise: 1, the engine compartment is soundproof, and a fire-proof soundproof barrier can be installed; The hood is insulated, and thermal insulation cotton can be installed. 2. Cleaning up the carbon deposits in the engine, especially in the air intake, throttle, spark plug and fuel injector, can reduce the self-noise. 3. Using semi-synthetic or fully synthetic oil instead of high-performance engine oil can reduce the consumption and noise of the engine itself. Synthetic oil is more effective, but the price is higher. 4. Keep the engine idling within the optimal speed range, and the noise will be less. For the EFI system, only the computer needs to be reset, and no other adjustments are needed.