Why does the engine noise become louder when stepping on the accelerator in a car?

[VonZoe]

The reasons why the engine noise becomes louder when stepping on the accelerator in a car include: engine overheating; internal engine issues, etc. Engine Overheating: If the engine operates for an extended period, causing the surface to overheat, the cooling system may develop problems. At this point, it is necessary to check the cooling system. If the cooling system has issues, it may lead to exhaust blockage because the vacuum tube is likely to break. At this time, steam or hot air may escape from the engine, resulting in abnormal noise. Internal Engine Issues: If there are internal engine problems, check the oil pressure gauge to determine if it is due to oil pressure issues, ignition problems, or internal valve blockage, etc.

[ReedMarie]

It's quite common for the engine noise to increase when stepping on the gas pedal, my old car does this too. When it was new, it was very quiet, but after five or six years, it roars whenever I press the accelerator. After inspection, it was found that the sealing ring at the exhaust pipe joint had aged, and the exhaust gas leakage made it particularly noisy. It could also be due to excessive carbon buildup; the engine has to work harder to produce power, naturally making more noise. If the engine oil is too thin or insufficient, it can also cause this issue, as poor lubrication leads to louder friction sounds between parts. Last time, I replaced the air filter, and it improved a lot. The old filter was clogged with dust, causing the engine to struggle with air intake. If you also feel that the car has weak acceleration, it's best to have someone check the chassis and muffler as soon as possible. You can first check for black oil stains at the exhaust pipe joint yourself.

[LeAiden]

The issue of the engine roaring when accelerating has been encountered several times. Last time when I checked my sister's car, it turned out to be due to aging ignition coils, with one cylinder misfiring out of the four, causing the noise. Worn-out spark plugs can also cause this, so it's necessary to check them after exceeding 30,000 kilometers. If the belt is loose or the tensioner is worn, it will produce a squeaking sound during acceleration. There was also an instance after heavy rain when the noise suddenly increased, and it turned out to be a perforated exhaust pipe. It's quite normal for rubber parts to age in older cars; if the engine mount buffer rubber cracks, the engine vibration noise directly transmits into the cabin. The sound increasing when climbing with the air conditioning on is normal, as the compressor increases the engine load. Long-term use of cheap gasoline can lead to carbon buildup, so it's recommended to add a bottle of fuel additive with every tank of gas.

[StRebecca]

Don't panic if your new car's engine noise increases when accelerating - it might just be resonance from a loose engine guard plate. Last month after scraping my undercarriage, the guard plate screws loosened causing a buzzing vibration when accelerating. Modified exhaust systems naturally produce louder sounds, especially when backpressure is insufficient. Engine noise can also increase if oil level is low or if you've exceeded the 5,000km maintenance interval. A loosely fastened air filter box may create puffing air leakage sounds. Aging power steering pumps can produce squealing noises during acceleration. For automatic transmissions, sudden RPM increase during hard acceleration downshifts normally creates louder sounds. Cold starts being noisy but quieting down after reaching normal operating temperature isn't problematic. If neutral revving shows smooth sound progression without abrupt changes, it's generally normal.