What Causes a Car's Power to Decrease After Running Continuously for Several Hours?

[JoshuaRose]

Possible causes include cooling system failure, followed by affected engine output, tire wear, and engine oil leaks. Below is relevant information about car maintenance: 1. Introduction to Car Maintenance: Car maintenance primarily includes servicing the engine system, transmission system, air conditioning system, cooling system, fuel system, power steering system, etc. 2. The Role of Car Maintenance: To maintain the vehicle's appearance and technical condition, eliminate potential hazards, prevent malfunctions, slow down deterioration, and extend the service life. 3. The Function of the Maintenance Light: It records the mileage of important components, promptly reminding the owner and maintenance personnel. If the owner replaces related components but fails to reset the maintenance light, it won't affect the vehicle's performance, but it may lead to inaccurate tracking of the new components' usage time for the next maintenance.

[DeKing]

Back when I ran an auto repair shop, I came across many cases of vehicles losing power after long-distance driving. The root cause is usually engine overheating triggering a chain reaction. For instance, engine oil thins out at high temperatures, reducing lubrication effectiveness and increasing friction resistance; the fuel pump becomes unstable under heat, leading to insufficient fuel supply; or the cooling system gets clogged or the radiator fan ages, resulting in inadequate heat dissipation—once temperatures spike, the electronic control module automatically limits speed to protect the engine. Before long trips, it's advisable to check the oil viscosity and coolant level, and take breaks to let the engine cool for half an hour. Additionally, a dusty air filter can hinder air intake efficiency, posing another risk—regular replacement helps prevent this.

[StAndres]

As a seasoned driver, I often feel my car lacks power after several hours of long-distance driving, with the accelerator pedal feeling sluggish. This could be due to the engine overheating, especially in summer when high temperatures thin out the engine oil, reducing its protective properties, or the continuous use of air conditioning adding extra load to the engine. Poor coolant circulation can cause temperatures to rise faster, naturally leading to a drop in power. Pulling over to let the engine cool down usually restores its performance. I recommend keeping an eye on the temperature gauge during long trips and avoiding full-throttle acceleration. Regular maintenance, such as cleaning carbon deposits and checking the fuel pump, is also crucial to prevent minor issues from escalating.

[LaIan]

My old car is over ten years old, and after driving continuously for several hours, there's noticeable power loss and increased engine noise. It's probably due to worn-out components operating unstably under high temperatures, such as decreased piston ring sealing leading to insufficient compression; or maybe the aging fuel system with clogged fuel lines causing poor fuel delivery; or the radiator's reduced efficiency accelerating overheating. Regular maintenance alone can't keep up with these issues, and I regret not replacing parts in time. Checking the transmission fluid and cooling fan regularly can help alleviate the symptoms.