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Will the Engine Make Abnormal Noises During High-Temperature Idling?

4 Answers
LaElla
07/29/25 8:02pm
Abnormal noises during high-temperature engine idling are considered abnormal phenomena, and the cause should be promptly identified and repaired. Causes of engine idling noises: Noises caused by excessive clearance. When factors such as lubrication, temperature, load, and speed are constant, the noise becomes more pronounced as the clearance increases. Wear and tear on certain engine components can lead to excessive clearance, resulting in noises such as piston and cylinder wall knocking sounds, or connecting rod bearing and journal impact sounds. Engine misfire primarily refers to one or more cylinders not functioning properly, typically characterized by: intermittent exhaust gas flow with noticeable shaking of the exhaust pipe, accompanied by clear "popping" or "thumping" sounds from the engine. This phenomenon is often related to ignition coil failure. Engine knocking noises, resembling startup knocking sounds, occur when the piston swings or shifts within the cylinder during up-and-down movement, causing its head or skirt to collide with the cylinder wall or head, producing abnormal noises. These can be further categorized as cold knocking, hot knocking, or both. Solutions for engine idling noises: There are many potential causes of engine noises, such as damaged injector seal rings allowing high-pressure gas leakage, faulty electromagnetic valves, air intake system leaks, or insufficient lubrication in the high-pressure fuel pump. Therefore, abnormal noises during vehicle idling can be seen as a signal of mechanical failure. In such cases, it is advisable to visit a professional service center to diagnose the cause and replace any damaged components in a timely manner.
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LeGrace
08/14/25 4:04pm
The engine indeed makes abnormal noises during high-temperature idling, which is common in many vehicles I've handled. High temperatures cause metal components to expand, such as the piston and connecting rod gaps becoming smaller, increasing friction and resulting in clicking or squeaking sounds. Engine oil thins out at high temperatures, reducing lubrication effectiveness and making bearing wear noises more noticeable. Issues in the cooling system, like damaged water pump bearings or loose fan belts, can also cause a humming sound. I've seen cases where owners ignored these signs, leading to engine overheating and failure, resulting in costly repairs. It's recommended to stop the vehicle immediately when the temperature is high and check the coolant and oil conditions. If the abnormal noises persist, seek professional diagnosis as soon as possible. For prevention, regular oil changes and cleaning the cooling system can significantly reduce risks and extend engine life.
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Carson
10/16/25 2:09am
My old car made strange noises when idling in the summer heat, and I heard a clicking sound that really worried me. High temperatures cause engine components to expand, and insufficient oil protection increases friction and noise. The fan or water pump might also make loud noises. I immediately stopped the car, waited for it to cool down, and checked, only to find the coolant was low. After refilling it, I drove to the repair shop. The mechanic said that delaying further could lead to a blown engine, which would be expensive to fix. So, I advise everyone not to ignore strange noises—they are safety warnings. Don’t idle for too long when the engine temperature is high, and perform simple checks like inspecting the oil dipstick. Regular maintenance of the cooling system ensures a safer drive.
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DeCamille
11/29/25 2:56am
High-temperature idle noise is quite common! When the engine heats up, insufficient metal expansion clearance makes piston slap noise noticeable. Engine oil thins at high temperatures, leading to poor lubrication and increased bearing noise. Issues with the fan or belts can also cause a humming sound. I enjoy analyzing these—abnormal noises are like the engine's distress signals, and high temperatures can cause significant damage. I advise fellow car enthusiasts to pay attention to unusual sounds when the coolant temperature is high and promptly check the coolant. Regular maintenance, such as changing engine oil and belts, can prevent problems. Don't underestimate abnormal noises—they may indicate serious faults.
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