What Causes Engine Shaking When the Car Fan is Running?

[AmyLynn]

Here are the specific reasons for engine shaking when the car fan is running: Suspension System Failure: The suspension system is primarily responsible for filtering out engine vibrations during operation. If there is an issue with the suspension, these vibrations will directly transmit to the steering wheel and the cabin, affecting driving. When the engine is idling, turning on the vehicle's electrical systems can also easily cause shaking. The engine's load increases due to the activation of electrical components, leading to a drop in idle speed. To compensate for the shaking caused by the idle speed drop, the engine will automatically increase the RPM. Unstable Oil Pressure: Check whether the fuel supply pressure and the intake pressure sensor are functioning normally. If the fuel pump's supply pressure is abnormal or the intake pressure sensor's readings are incorrect or malfunctioning, it can cause the vehicle body to shake. Cold Start: The main reason for vehicle shaking during a cold start is incomplete fuel combustion, resulting in insufficient power. Low ignition energy means that during startup, when the temperature of fuel and lubricant is low, more fuel is needed to meet power demands. Over time, the spark plug's electrode gap gradually widens, leading to decreased ignition energy and poor fuel atomization, which causes the vehicle body to shake. Additionally, aging ignition coils, spark plug high-voltage wires, or electrical leakage can also reduce ignition energy.

[DaisyAnn]

I've encountered the issue of engine shaking when the fan is running several times. The main cause is the excessive vibration generated by the rotating fan, which is transmitted to the engine block. Common reasons include unbalanced or deformed fan blades, which can cause eccentric wobbling when spinning. If the fan motor is faulty, unstable current can also pull on the engine. When the engine's support components, such as the engine mounts, are aged or damaged, they can't effectively dampen the vibrations, leading to body shaking. The cooling system requires significant electrical power when the fan is operating, which may increase the engine load. After parking, I can simply observe the fan's operation for any abnormal noises or wobbling. The shaking issue must be addressed promptly to avoid damaging the engine's core components and increasing repair costs. It's recommended that car owners regularly check the fan's balance and the condition of the support mounts, and seek professional repair if any abnormalities are found.