Why is the startup sound of BMW 1 Series so loud?

[VanRowan]

The phenomenon of a very loud startup sound in the BMW 1 Series occurs because, after the car has been parked for a long time, the engine oil slowly returns to the bottom of the oil pan. This results in insufficient lubrication in the upper part of the engine during startup, leading to the loud startup sound. Below is more information about the BMW 1 Series: 1. The BMW 1 Series is a model series from BMW, with the revamped version making its first appearance at the Geneva Motor Show in 2015. 2. The new BMW 1 Series integrates sporty elements into every detail of its design, inheriting the characteristics of BMW cars and perfectly showcasing the functionality of the hatchback model and BMW's typical driving performance. 3. The BMW 1 Series is a compact luxury car, equipped with five genuine leather seats. Its top speed varies depending on the powertrain configuration, reaching up to 213 km/h, demonstrating outstanding performance.

[DeEzra]

I've been driving a BMW 1 Series for over a year, and recently the morning startup sound has been particularly loud, sounding like a tractor roaring. I asked some experienced driver friends, and they said this is normal for cold starts—BMW engines are designed this way to warm up quickly and protect components, so the startup can be a bit noisy, especially in cold winter temperatures. However, if there's persistent loud noise or metallic grinding sounds, it's necessary to check if the starter motor, exhaust system, or engine chain is aging or worn. I regularly maintain my car, change the oil, and check the battery, which has significantly reduced the noise. Remember, don't ignore unusual sounds—get them diagnosed early at a professional repair shop to avoid costly major repairs. Driving this car is a lot of fun, and learning about these minor issues is quite fulfilling.

[VonCassidy]

I have some knowledge about cars, and there are various reasons why the BMW 1 Series makes loud starting noises. During cold engine starts, adjustments to fuel injection and ignition timing for lubrication and component protection can increase noise, which is normal. However, if the noise remains loud in warm weather or after starting, it could indicate issues with the valve system, starter wear, or exhaust leaks. You can perform a simple self-check by listening to the source of the noise: if it comes from the rear of the engine, focus on the starter motor; if it's from the front, pay attention to the chain tensioner. Remind the technician to check these during every maintenance service, avoid using low-quality engine oil, and ensure the engine runs smoothly—that's key. Driving a BMW requires attentiveness; preventing small issues is the most cost-effective approach.

[DelAlexandra]

My BMW 1 Series makes loud starting noises. Based on experience, there are usually two common causes: first, the engine sound normally increases when starting a cold car; second, the exhaust muffler might be damaged or the starter motor could be faulty. Initially, if the noise disappears quickly, it's fine, but if it persists, action is needed. A faulty starter motor usually comes with slow starting, while exhaust leaks produce a hollow sound. Taking it to a 4S shop for a quick check can resolve the issue promptly. Regular oil changes in maintenance can help avoid further noise problems.