What Causes a Dull, Weak Engine with Excessive Noise?

[FelicityLynn]

It may be due to prolonged use causing damage or aging of the foot pads, resulting in loss of shock absorption. Below is an introduction to the reasons for excessive engine noise: 1. Excessive engine oil: There is a standard for oil filling—more is not always better. If too much oil is added, it can create greater resistance to the crankshaft's rotation, affecting power output and increasing fuel consumption. The amount of oil entering the combustion chamber increases significantly, leading to more carbon buildup in the combustion chamber, increasing piston movement resistance and reducing engine power. It can also alter the air-fuel ratio in the combustion chamber, increasing the likelihood of knocking and resulting in louder noise. 2. Moderate carbon buildup: Over time, old engine oil becomes thinner, and carbon deposits accumulate more. Thinner oil is more prone to oil leakage, causing further carbon buildup. When new oil is added, the engine may not adapt to the oil viscosity immediately, potentially raising the engine speed and causing louder noise. It is recommended to use high-grade gasoline and maintain a high engine speed, preferably above 2,500 RPM, for at least one tank of high-grade gasoline to see improvement. Preventive cleaning is also an option. 3. Suitable oil viscosity: Different grades of engine oil have different characteristics, such as low-temperature starting performance and high-temperature wear resistance and adhesion. The viscosity of engine oil is inversely proportional to temperature. When the engine is cold, the oil viscosity is higher. If the selected oil is too thick, it can impose additional strain on the starter motor and battery.

[BriellaLee]

I've been driving this car for several years, and recently I've noticed that the engine noise is particularly loud, and it feels sluggish and lethargic, lacking power when driving, as if an old ox is pulling the cart. At first, I thought it was just the engine getting old, but upon closer consideration, there might be several reasons: First, there could be an issue with the fuel system—the fuel injectors might be clogged, or the fuel lines could be obstructed, leading to insufficient fuel supply. Second, the ignition system might be faulty, with aging spark plugs or a malfunctioning ignition coil, resulting in poor ignition. Third, there could be mechanical problems, such as worn piston rings or excessive clearance in the crankshaft bearings, causing increased internal friction and loud noise. Fourth, the engine oil might be subpar—either it hasn't been changed for too long or the oil level is too low, leading to poor lubrication and strained engine operation. Additionally, the air filter might be too dirty, restricting airflow and affecting combustion. Last time I went for car repairs, the mechanic reminded me to change the engine oil regularly and check the spark plugs—it saves money and hassle, and prevents regrets from breaking down halfway. Paying attention to changes in engine sound during daily use and maintaining the car well can eliminate most problems.

[GenevieveLynn]

I just bought a used car and immediately encountered a roaring engine that sounds dull and lacks power, which is really frustrating. I think common issues include fuel system problems, such as insufficient fuel pump pressure or a clogged filter, preventing fuel from reaching the engine and making it struggle; then there's the ignition system, with worn spark plugs or shorted high-voltage wires causing unstable ignition and unpleasant noises; also, exhaust system leaks or a clogged catalytic converter can hinder exhaust flow and reduce power; mechanical issues like problems with the camshaft or valve clearance can cause excessive friction and a buzzing noise. I’ve always enjoyed tinkering with cars, so I suggest starting with the basics: check the fluid levels yourself, see if the engine oil is black, and try replacing the spark plugs; if that doesn’t work, take it to a professional shop to diagnose whether the ECU sensors are throwing any error codes. After sorting it out, driving feels much smoother—don’t let small issues turn into big problems.

[LuciaLynn]

Having driven for so many years, I've seen plenty of cases where engines are noisy and lack power. Usually, insufficient or degraded engine oil leads to poor lubrication and increased noise; excessive fuel impurities clog the fuel supply system, making the engine sluggish; aging ignition coils result in weak sparks and reduced output. The key is regular maintenance: check the engine oil and spark plugs, and replace the air filter. Safety comes first—don't take risks on the road.