Does the Fan Run at Idle Speed?

2 Answers
Kinsley
09/04/25 7:56am
Generally, the car fan starts running after about 10 minutes at idle speed. Below is an introduction to the fan behavior under idle conditions: 1. The operation of the fan at idle depends on the rate of water temperature rise, which varies from car to car and under different conditions. The time is slightly shorter in summer and longer in winter. When the car is moving, the time is also slightly shorter. 2. Older cars running the air conditioning at idle can be more damaging to the car. In older cars, the engine cooling fan is controlled by the engine crankshaft speed. At idle, the engine speed is low, and the cooling fan speed is also lower. 3. When the engine temperature rises, the water temperature also increases, which can cause some degree of damage to the car engine. 4. For cars produced in the current stage, running the air conditioning at idle does not cause much damage. Modern car engine cooling fans are powered by the battery and automatically adjust their speed based on the engine temperature. If the idle time is long, you can clearly hear the noise from the engine compartment fan becoming louder, which is actually due to the increasing fan speed.
Was this review help?
5
0
Share
VonVincent
09/16/25 8:42am
After years of repairing cars, I've found that whether the fan runs at idle depends on temperature. The fan primarily dissipates engine heat and is controlled by electronic systems, such as temperature sensors. Idle means low engine RPM—if the engine isn't hot (like during cold starts or in low-temperature conditions), the fan may not run. However, in traffic jams, with AC on, or during hot weather, the fan often activates at idle to prevent overheating damage. Once, while inspecting a customer's car, the fan wasn't running at idle—turned out to be a faulty temperature sensor, which was replaced to fix it. I recommend regular checks of fan operation; don't wait for major issues to repair.
Was this review help?
6
3
Share
Expand All
More Forum Discussions

Can Sunroof Leakage Be Claimed on Insurance?

Sunroof leakage cannot be claimed on insurance. Here is some relevant information about sunroofs: Functions of a sunroof: It can quickly lower the temperature, eliminate fogging, and rapidly exchange fresh air. Opening the sunroof while driving can quickly increase the air circulation inside the car, thereby improving ventilation and air exchange in the cabin. Precautions regarding sunroofs: Open the sunroof in traffic jams to prevent exhaust fumes from entering the car. During traffic jams, when all vehicles are stationary, exhaust fumes inevitably disperse in the air. Open the sunroof after exposure to sunlight to balance the interior temperature. In hot summers, after the car has been exposed to the sun, the interior temperature becomes very high. At this time, the owner should promptly open the sunroof.
16
4
Share

What are the two styles of Mercedes-Benz keys?

All Mercedes-Benz cars have the same key. The two styles likely refer to the mechanical key and the remote key. Key classification: Car keys are divided into two types, one without an anti-theft chip and the other with an anti-theft chip. Keys with anti-theft chips are commonly found in some low-end models and don't even have a remote control, which is now rare. Smart key: A smart key is equivalent to a small radio wave transmitter. The chip inside the key contains a unique ID code that matches the car. When the smart key emits a radio wave, it is received by the car. After confirmation by the car's anti-theft system control unit, the key is recognized, and then the door can be opened and the engine started.
7
1
Share

What audio system is used in the Volkswagen Golf 6?

Volkswagen Golf 6 is equipped with different brands of car audio systems depending on the model. The flagship version is equipped with a Dynaudio sound system, while other models come with the factory-installed audio system. When selecting an audio system: First, identify the brand and ensure that the merchant has the designated agency license authorized by the manufacturer of the audio equipment, as well as after-sales service capabilities and quality assurance measures. It is advisable to gradually upgrade the audio system: Generally, it is not recommended to go for the highest-end car audio system at once, as premium car audio systems are expensive. Instead, enjoy the listening pleasure brought by progressively upgrading to higher-level audio systems.
20
1
Share

Can the plastic cover on the outside of the headlight be replaced?

The plastic cover on the outside of the headlight can be replaced. Impact of the headlight cover: If the headlight cover of a car is cracked, it needs to be replaced promptly. If not replaced, the headlight will lose its seal, leading to moisture inside the headlight, which affects car lighting. In rainy conditions, water may even enter, potentially causing a short circuit and damaging the headlight. Replacing the entire headlight assembly: The headlight cover can be replaced by yourself. If the headlight cover is damaged, a 4S shop will usually replace the entire headlight assembly because original headlight covers are not available. It's important to note that replacing the entire headlight assembly is a complex and time-consuming process.
19
3
Share

Why Was the Volkswagen Sharan Discontinued?

Volkswagen Sharan has only ceased production but not sales. Basic information about the Volkswagen Sharan: 1. Model Configuration: Contrary to the current trend of electronic cockpits, the Sharan features a manually adjustable driver's seat, a single-disc CD player, and non-independent rear air conditioning controls. For an MPV priced at nearly 400,000 yuan, the surface-level configurations may seem somewhat unconvincing. 2. Interior Introduction: The Sharan adopts a 2+3+2 seating arrangement, which means there is no central aisle for third-row passengers to access. Although the vehicle width exceeds 1.8 meters, due to its slightly inward-curving arc design, shoulder and headroom may be somewhat compromised when fully loaded. However, for an MPV measuring 4.6 meters in length, the Sharan's space utilization is quite impressive.
15
0
Share

Will the Chery E3 emit black smoke from the exhaust pipe after upgrading from a 4-hole to an 8-hole fuel injector?

No, black smoke from the exhaust pipe indicates excessive carbon particles in the exhaust, which can only occur due to incomplete combustion of fuel. Reasons for incomplete combustion: The primary cause of incomplete combustion is an overly rich fuel-air mixture. Solutions: Check if there is insufficient air intake, mainly by inspecting whether the air filter is clogged or if the air flow meter is damaged. Examine the fuel injector's performance to see if poor atomization is the issue, and also pay attention to fuel quality. Check the cylinder compression for any leaks and whether there is excessive carbon buildup on the valves or in the combustion chamber.
20
5
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.