What Causes Abnormal Noise When Accelerating the Engine?

[WilliamMarie]

Engine abnormal noise when accelerating may be caused by: 1. Excessive cam wear causing tappet jumping during operation; 2. Impact between the rocker arm head of overhead valves and valve top; 3. Excessive carbon buildup in valve guides; 4. Detachment of valve spring seats; 5. Damage to hydraulic tappets or tappet cylinders; 6. Aging or loosening of engine mounts. Engine maintenance methods include: 1. Regularly changing engine oil and filters; 2. Using appropriate quality grade lubricants; 3. Periodic cleaning of the radiator; 4. Regular replacement of air filters, oil filters, and fuel filters; 5. Maintaining good crankcase ventilation with regular cleaning; 6. Periodic cleaning of the fuel system.

[Ron]

Well, I've driven quite a few cars and found that abnormal engine noises during acceleration are usually caused by common mechanical issues. The most frequent culprit is ignition system failure, such as worn spark plugs or damaged ignition coils. When you accelerate, they can't ignite the air-fuel mixture promptly, leading to detonation or knocking sounds in the cylinders. The belt system is another critical area – a loose or worn timing belt will produce squealing or rattling noises, especially noticeable during hard acceleration. Fuel system problems shouldn't be overlooked either. Clogged fuel injectors or insufficient fuel pump pressure can make the engine "gasp," creating unusual sounds. Exhaust leaks, like cracks in the piping, may cause buzzing noises. I always recommend immediate diagnosis at a repair shop – don't ignore these minor issues as they might escalate into major repairs. Regular maintenance checks on these components can prevent most abnormal noises. Remember, safety first – unusual sounds may indicate potential engine failure risks.

[Theodore]

I noticed a strange noise when the car accelerates, which really worries me. As a long-term car owner, I believe the causes mostly stem from daily wear and tear. Issues with piston rings or valve clearance can lead to engine shaking and noise, especially when the throttle is pressed and pressure increases. Another point is the air system—for example, a dirty or clogged air filter can restrict airflow, causing the engine to work inefficiently and produce a sputtering sound. Insufficient lubrication is also common; low or poor-quality engine oil, along with worn crankshaft bearings, can create friction-related noises. Sometimes, it's an electronic sensor malfunction, such as a faulty knock sensor, which misleads the computer into advancing ignition timing, resulting in a metallic knocking sound. What I often do is stop and inspect the car myself—like listening to the direction of the noise and noting it down to describe to the mechanic—to avoid driving blindly. Regularly changing the oil and checking the belts can significantly reduce risks and extend the engine's lifespan. Don’t delay—safe driving relies on careful observation.

[McGraham]

Engine noise during acceleration, I believe the primary issue is part aging. Worn spark plugs often cause metal collision sounds, and ignition delay leads to knocking. Loose or broken belts are also contributing factors, producing squeaking noises during high-speed acceleration. Fuel pump failure affects fuel supply stability, generating a buzzing sound. It is recommended that car owners regularly maintain key components, such as checking spark plugs and belts every 5,000 kilometers. Ignoring these may increase the likelihood of accidents.