Power Steering Decoded: Understanding Types, Failures, and Maintenance for Smooth Steering

How Does A Power Steering work?

Power steering is a system in vehicles that assists the driver in steering by reducing the effort required to turn the steering wheel. The basic operation of power steering involves the following components:

Steering Wheel: The driver controls the direction of the vehicle by turning the steering wheel.

Power Steering Pump: The power steering pump is typically driven by the vehicle's engine. It creates hydraulic pressure that powers the steering system.

Hydraulic Fluid: Power steering systems use hydraulic fluid, often referred to as power steering fluid, to transmit and amplify the force applied by the driver to the steering wheel.

Power Steering Gear or Rack: The hydraulic pressure generated by the power steering pump is directed to a power steering gear or rack, depending on the type of steering system.

Power Assist Mechanism: Within the power steering gear or rack, there is a power assist mechanism that multiplies the force applied by the driver to make steering easier.

Control Valve: The control valve in the power steering system regulates the flow of hydraulic fluid, determining the level of power assistance based on the driver's steering input.

When the driver turns the steering wheel, it sends a signal to the power steering pump to start generating hydraulic pressure. The hydraulic fluid is then pressurized and directed to the power assist mechanism in the steering gear or rack. The power assist mechanism multiplies the force applied by the driver, making it easier to turn the wheels.

In traditional hydraulic power steering systems, the level of power assistance remains constant. However, in modern electric power steering systems, sensors and control modules detect the driver's steering input, vehicle speed, and other factors to provide variable assistance, adjusting the level of power assistance based on driving conditions.

Figure 1: Picture courtesy of  https://mechasource.blogspot.com/2019/04/an-introduction-to-power-steering-pump.html

The Three Types Of Power Steering Pumps

There are primarily three types of power steering pumps commonly used in modern vehicles: hydraulic power steering pumps, electric power steering pumps, and electro-hydraulic power steering pumps. Let's briefly explain each type and discuss their pros and cons:

Hydraulic Power Steering Pump:

This type of pump is driven by the vehicle's engine through a belt and pulley system.

It uses hydraulic pressure generated by a rotary vane or gear mechanism to assist in steering.

Pros:

• Provides strong and consistent power assist, especially at low speeds.
• Relatively simple and robust design.
• Suitable for larger vehicles and heavy-duty applications.

Cons:

• The pump continuously draws power from the engine, which can reduce overall fuel efficiency.
• Requires regular maintenance, such as fluid checks and belt replacements.
• Can be prone to leaks and noise issues over time.

Electric Power Steering Pump:

Instead of being driven by the engine, this type of pump is powered by an electric motor.

It uses sensors and a control module to determine the amount of power assistance required.

Pros:

• Offers better fuel efficiency since it only operates when assistance is needed.
• Provides more precise and adaptable power assistance.
• Generally lighter and more compact, allowing for easier installation in vehicles.

Cons:

• Relies on electrical power, so a failure in the electrical system can result in a loss of power steering.
• In rare cases, an electric power steering pump failure can lead to a sudden loss of steering assist.
• May not provide the same level of steering feel as hydraulic systems, which some drivers prefer.

Electro-Hydraulic Power Steering Pump:

This type combines the characteristics of both hydraulic and electric power steering systems.

It utilizes an electric motor to drive a hydraulic pump, which then generates the necessary hydraulic pressure.

Pros:

• Offers a balance between the strong power assist of hydraulic systems and the energy efficiency of electric systems.
• Can provide variable power assist based on driving conditions, improving fuel efficiency.
• Maintains some of the hydraulic system's robustness and familiarity.

Cons:

• The system can be more complex and potentially more expensive to manufacture and maintain.
• Like hydraulic systems, it relies on belts and pulleys, which require regular inspection and replacement.
• The system's performance and efficiency can vary depending on the specific design and implementation.

It's important to note that the availability and specific usage of these power steering pump types can vary across different vehicle models and manufacturers.

Symptoms Of A Failing Power Steering Pump

Early symptoms of power steering pump failure can vary depending on the type of pump. Here are some common early warning signs for each type:

Hydraulic Power Steering Pump:

• Whining or moaning noise: A noticeable noise, especially when turning the steering wheel, can indicate a problem with the pump.
• Difficulty in turning the wheel: Stiff or heavy steering, especially at low speeds, may suggest a failing pump.
• Fluid leaks: Look for signs of power steering fluid leaking around the pump or other components of the system.
• Increased steering effort: If the steering wheel requires more effort to turn than usual, it could indicate a failing pump.
• Reduced power assist: Gradual loss of power assistance, resulting in harder steering overall, may be a sign of pump failure.

Electric Power Steering Pump:

• Loss of power steering assist: If the power steering suddenly stops working or becomes intermittent, it may indicate an issue with the electric pump or its electrical components.
• Warning light: Many modern vehicles have a power steering warning light that illuminates when there is a problem with the electric power steering system.
• Unusual noises: Grinding, whining, or humming sounds when turning the wheel can be a sign of a failing electric power steering pump.
• Steering wheel vibration: Excessive vibration in the steering wheel, particularly during low-speed maneuvers, may indicate a problem with the electric power steering system.

Electro-Hydraulic Power Steering Pump:

• Similar symptoms to hydraulic power steering pump failure: Since the electro-hydraulic system combines hydraulic and electric components, the early symptoms may resemble those of a hydraulic power steering pump failure. These include whining noise, difficulty turning the wheel, fluid leaks, and increased steering effort.
• Loss of power assist: If the power steering assist becomes inconsistent or stops working altogether, it could be a sign of an issue with either the hydraulic or electric components of the system.

It's worth noting that these symptoms can also be caused by other problems within the power steering system, such as a damaged belt, low fluid levels, or a malfunctioning pressure hose. If you experience any of these symptoms, it's recommended to have your vehicle inspected by a qualified mechanic to diagnose and address the specific issue.

How To Prolong The Life Of Your Power Steering Pump

To prolong the life of a power steering pump, you can follow these guidelines:

Regular Maintenance: Adhere to the manufacturer's recommended maintenance schedule for your vehicle, including power steering system inspections and fluid changes. Regular maintenance helps keep the pump and the entire system in good working condition.

Check Power Steering Fluid: Monitor the power steering fluid level regularly and ensure it is within the recommended range. If the fluid is low, top it up using the appropriate fluid specified in your vehicle's manual.

Use the Correct Fluid: Always use the type of power steering fluid recommended by the vehicle manufacturer. Using the wrong fluid can damage the pump and other components of the system.

Avoid Overloading the System: Do not place excessive strain on the power steering system by turning the steering wheel sharply when the vehicle is stationary or while it is moving slowly. This can put unnecessary stress on the pump and lead to premature wear.

Be Gentle with the Steering: Avoid jerking the steering wheel or forcing it beyond its normal range of motion. Smooth and controlled steering inputs can help reduce strain on the pump and extend its lifespan.

Keep Belts and Pulleys in Good Condition: Inspect the drive belts and pulleys connected to the power steering pump regularly. Ensure the belts are properly tensioned and free from cracks or signs of wear. Replace worn belts and damaged pulleys promptly.

Prevent Fluid Contamination: Keep the power steering fluid clean and free from contaminants. Avoid introducing dirt or debris into the fluid reservoir when checking or topping up the fluid.

Address Leaks Promptly: If you notice any power steering fluid leaks, have them inspected and repaired as soon as possible. Leaks can cause the pump to work harder, leading to premature failure.

Professional Inspection: If you experience any unusual noises, vibrations, or difficulties with the power steering system, have it inspected by a qualified mechanic to diagnose and address any potential issues early on.

By following these recommendations, you can help extend the life of your power steering pump and maintain the overall health of the power steering system in your vehicle.

How We Can Help

If you're facing issues with your power steering system, rest assured that you're not alone. At StartMyCar, we understand the frustration and inconvenience that can arise from power steering problems. We're here to assist you in finding a suitable replacement part for your vehicle.. Whether it's a power steering pump, belt, or any other component, we have the knowledge and resources to help you get your vehicle back on the road smoothly.