What Are the Causes of Power Steering Pump Humming Noise?
2 Answers
The causes of power steering pump humming noise are: 1. The sound of the pressure relief valve during operation, which is normal; 2. The filter screen is clogged, causing the pump to make noise; 3. Air in the power steering pump, oil leakage in the high-pressure oil pipe, or failure of the oil reservoir; 4. Low power steering fluid, simply add more fluid. Reasons for abnormal noise in the car power steering pump: 1. Oil leakage from the power steering pump, resulting in low oil level; 2. Poor lubrication of the power steering pump when cold, leading to internal wear and abnormal noise; 3. Loose installation of the power steering pump, causing noise during operation. The car power steering pump mainly adopts hydraulic power assistance, electric power assistance, electric power steering, mechanical hydraulic power assistance, and electro-hydraulic power assistance.
I've handled many cases of power steering pump whining, which are usually caused by insufficient power steering fluid or air entering the system. When the fluid level is low, the pump runs dry, protesting with a whining sound like a water pump without water, which can be quite alarming. If the hoses are aged or cracked, allowing air to leak in, bubbles form in the fluid circuit, causing unstable pump operation and noise. Loose or worn belts can also lead to pulley vibration and resonance noise. Additionally, worn bearings inside the pump are a common issue, especially in older or poorly maintained vehicles. My recommendation is to first check the dipstick to ensure the fluid level is within the standard range when the engine is cold or hot. If the fluid is dirty or degraded, it should be replaced. Ignoring the issue can lead to louder whining noises, potential pump burnout, or sudden steering failure, which is extremely dangerous. A quick fix: try topping up the power steering fluid yourself—if the noise goes away, that's an easy solution. If not, have a technician inspect the belt tension and pump condition immediately to avoid worsening steering difficulties.
