Why is the car's steering wheel hard to turn?

[IsabelleAnn]

Common reasons for a suddenly heavy steering wheel include: 1. The most common cause is dirty power steering fluid. Dirty power steering fluid can make the steering wheel increasingly harder to turn. If the fluid level is low, this issue can also occur. In such cases, it's necessary to perform timely maintenance or add/replace the power steering fluid. 2. In a mechanical hydraulic power steering system, if any mechanical component malfunctions, it can also lead to a sudden difficulty in turning the steering wheel. 3. Another reason involves the electro-hydraulic power steering system, which differs from the mechanical system mainly in the driving method of the oil pressure pump—the electro-hydraulic system uses an electrically driven electronic pump. One scenario is that repeatedly turning the steering wheel while stationary or at low speeds places a significant load on the power steering system, which can cause the steering gear to overheat and enter a protective mode, resulting in heavy steering. This usually resolves after cooling down, which is a normal phenomenon.