What Causes Loud Engine Noise After Vehicle Maintenance?
3 Answers
Here are the reasons for loud engine noise after vehicle maintenance: 1. Using engine oil of different brands or specifications. 2. Excessive carbon buildup or overfilling of engine oil. 3. Incomplete removal of the original engine oil. 4. Changing the type of engine oil may cause noise. Here are solutions to reduce loud engine noise: 1. Use specialized equipment to perform a no-disassembly cleaning of the engine lubrication system. 2. Replace with the appropriate or higher-grade engine oil suitable for the vehicle model. 3. Add an appropriate amount of anti-wear additive for wear resistance and repair. 4. It is recommended to lift the vehicle and check if there is a heat shield between the exhaust pipe and the ground. The noise may be caused by aging of the heat shield, which can be resolved by replacement or removal.
A while after my car's maintenance, the engine noise became much louder. At first, I thought it was normal, but after driving for a few days, it felt off—kind of like a rumbling sound. Later, I took it to a mechanic for inspection, and it turned out that the wrong type of engine oil was used during the oil change. The viscosity was too high, causing insufficient lubrication and increased engine friction, which led to the noise. Similar issues include a friend’s car where the air filter wasn’t installed properly, leading to dust clogging, or a loose exhaust pipe connection causing vibration noises. In short, increased noise after maintenance isn’t a minor issue—it can accelerate part wear. I recommend returning to the shop for a recheck as soon as possible, unlike me who delayed it, to avoid costly engine repairs later.
Why is the engine louder after maintenance? I have some experience to share. Common reasons include issues with oil changes, such as using oil with unsuitable viscosity or insufficient quantity, which can make the engine work harder and produce more noise. Additionally, improperly installed parts during replacement can also have a significant impact, like loose belts or misaligned filters. You can troubleshoot yourself: open the engine compartment and listen to where the noise is coming from, whether it's the left or right side; check the dipstick to see if the oil level is within the standard range. Remember, using the correct oil is crucial, as different car models require different oil specifications. Choosing the wrong one can alter the engine sound. Address the issue promptly to avoid damaging the engine.
