What Causes the Steering Wheel Noise When Turning in Audi A6L?
2 Answers
Audi A6L steering wheel noise when turning may be caused by: aging of the steering tie rod ball joint; leakage of the steering gear dust cover; or dirty power steering fluid. The power steering system is divided into mechanical hydraulic power steering system and electro-hydraulic power steering system: 1. Mechanical Hydraulic Power Steering System: (1) Main Components: The mechanical hydraulic power steering system generally consists of a hydraulic pump, oil pipes, pressure and flow control valve body, V-type drive belt, oil reservoir, and other components. (2) Working Principle: This system operates regardless of whether the vehicle is turning or not. At low speeds with large steering angles, the hydraulic pump needs to output more power to provide greater assistance, which to some extent wastes resources. Driving such a vehicle, especially during low-speed turns, makes the steering feel heavier and the engine work harder. Additionally, the high pressure of the hydraulic pump can easily damage the power steering system. Moreover, the mechanical hydraulic power steering system, composed of the hydraulic pump, pipelines, and oil cylinder, always remains operational to maintain pressure, whether steering assistance is needed or not, resulting in higher energy consumption. This is another reason for resource wastage. Generally, economical cars use the mechanical hydraulic power steering system more frequently. 2. Electro-Hydraulic Power Steering System: (1) Main Components: Oil reservoir, power steering control unit, electric pump, steering gear, power steering sensor, etc., where the power steering control unit and the electric pump are integrated into one structure. (2) Working Principle: The electro-hydraulic power steering system overcomes the shortcomings of the traditional hydraulic power steering system. The hydraulic pump it uses is no longer directly driven by the engine belt but by an electric pump. All its working states are calculated by the electronic control unit based on signals such as vehicle speed and steering angle to achieve the optimal state. Simply put, during low-speed and large steering angles, the electronic control unit drives the electro-hydraulic pump to operate at high speed, outputting greater power to make steering easier for the driver. When the car is driving at high speed, the hydraulic control unit drives the electro-hydraulic pump to operate at a lower speed, saving some engine power without affecting the need for high-speed steering.
I also encountered the issue of steering wheel noise when turning in my Audi A6L. The sound resembled rubber friction or squeaking, especially noticeable during low-speed turns. I suspect it might be due to loose bearings in the steering column or insufficient lubrication—Audi's steering system is quite precise, and wear in ball joints or tie rods could also cause such noises. Once during winter, the noise became more frequent, but it went away after a simple lubrication at the shop. I recommend checking the power steering fluid level and topping it up if low. If the noise comes from around the steering column, it could be a bearing issue. Don’t ignore it—poor steering can compromise driving safety. During regular maintenance, have a mechanic inspect the dust boots and connection points to prevent bigger issues with minor expenses.
