What Causes the Abnormal Noise When the Car Just Starts?
4 Answers
The reason for abnormal noise during cold start is: The internal gears of the starter lose lubrication, affecting the timely return of the gears. Causes: When starting the engine, the starter rotates to drive the flywheel, thereby starting the engine. At this time, the engine speed is driven by the starter, so the engine speed is lower than the starter speed. When the engine speed exceeds the starter speed after starting, the ignition switch is manually operated to cut off the power, and the starter is turned off. Due to the internal dirtiness of the starter and the failure of the lubricating oil, the flywheel engine forcibly drives the starter to operate at its own speed. Since there is a speed difference between the two, this causes the starter to produce noise. Methods to Eliminate the Noise: The noise will only stop when the starter reaches the same thermal state as the engine, but in severe cases, the noise will occur every time the engine is started. To remove this noise, simply clean and maintain the starter or replace the starter.
As someone who frequently tinkers with cars, I've noticed that strange noises upon startup are often related to the belt system. The issue becomes more pronounced in cold weather due to rubber aging or loosening, causing squeaking sounds from friction during startup. Another common cause is wear in the tensioner or idler pulley bearings, which produces a clicking or rattling noise. When the engine first starts, the oil hasn't warmed up yet, increasing dry friction between metal components and amplifying the noise. I'd first check the belt tension by pressing on it to see if it's too loose, then inspect the bearings for any wobbling. If it's something I can handle myself, I might replace the belt or apply lubricant as a temporary fix. However, DIY repairs come with risks, so regular maintenance is best: inspect or replace belts every two years and monitor oil levels during each service. Ignoring these issues can escalate the noise, and one day, a seized component could leave you stranded. Safe driving comes first—early detection and action save both time and money.
Over years of driving, I've encountered several instances of abnormal startup noises. The first time was on a winter morning when the car squealed upon starting—turned out the drive belt was loose, and the noise diminished as the engine warmed up. Later, I learned that when belts age or get contaminated with oil, the initial high load during startup makes the friction noise particularly noticeable. Bearing issues are also common; for example, a faulty tensioner pulley bearing can cause a rattling sound when the engine runs. Insufficient oil leads to inadequate lubrication, exacerbating metal friction noises during startup. My advice: first, identify the noise source—if it's coming from the front, it's likely the belt system; if from the side, it might be alternator-related. A quick test: preheat the engine for a few minutes before a cold start—if the noise lessens, it's normal; otherwise, head to the repair shop promptly. Regular maintenance, like frequent oil changes, helps prevent issues. Don't ignore abnormal noises—delaying repairs can lead to costlier component damage.
There's noise when the car just starts, I think it shouldn't be ignored. It could be a squeaking sound from a loose belt, or a clicking noise from bearing wear. During cold starts, the oil is cold, increasing friction and noise. Belt system issues are the most common; check the belt tension yourself and adjust if it's too loose. Topping up low oil levels can help alleviate the problem. If the abnormal noise continues to increase, it's a warning sign—stop immediately to inspect or send for repair. Regular maintenance, such as frequent belt and oil changes, can prevent these issues.
