Nissan Altima How To Properly Pressurize Steering System

Power steering systems, while seemingly simple, are vital for comfortable and safe vehicle operation. A properly pressurized and functioning power steering system allows you to effortlessly maneuver your Nissan Altima, especially at low speeds. Conversely, a poorly pressurized or air-locked system can result in heavy steering, noise, and even damage to the power steering pump. This guide provides an in-depth explanation of how to properly pressurize the steering system on your Altima, ensuring optimal performance and longevity.

Background: Altima Power Steering System Basics

The Nissan Altima, depending on the year and trim, typically employs a hydraulically assisted power steering system. This means a belt-driven power steering pump (PSP) generates hydraulic pressure, which is then used to assist in steering. Let's break down the key components:

• Power Steering Pump (PSP): The heart of the system, driven by the engine's accessory belt. It draws power steering fluid (PSF) from the reservoir and pressurizes it.
• Power Steering Fluid Reservoir: Stores the PSF and often includes a filter to remove contaminants.
• High-Pressure Hose: Carries the pressurized PSF from the pump to the steering gear (also known as the steering rack).
• Steering Gear/Rack: Contains a valve that directs the pressurized PSF to either side of a piston, assisting the driver's steering input.
• Low-Pressure Return Hose: Returns the PSF from the steering gear back to the reservoir.
• Steering Linkage: Connects the steering gear to the wheels, translating the rotational motion of the steering wheel into the linear motion that steers the vehicle.

Understanding these components is crucial for diagnosing and addressing any power steering issues. Modern Altima's also use Electronic Power Steering (EPS) systems on some models. This article focuses on the hydraulic power steering system.

Technical Breakdown: How to Properly Pressurize the System

Pressurizing the system after maintenance (like replacing a hose, the pump, or flushing the fluid) is essential to remove air that may have entered the system. Air in the system will compress under pressure, leading to inconsistent steering feel and potential pump cavitation. Here's a step-by-step guide:

1. Preparation

• Safety First: Wear safety glasses and gloves. Power steering fluid can be irritating. Work in a well-ventilated area.
• Tools and Materials: You'll need:
  • New power steering fluid (check your owner's manual for the correct type; using the wrong fluid can damage the system). Nissan PSF is typically recommended.
  • Funnel
  • Rags or shop towels
  • Jack and jack stands (optional, but can make access easier, particularly if you want to bleed the system with the front wheels off the ground)
  • Wheel chocks
• Vehicle Preparation: Park the vehicle on a level surface, engage the parking brake, and chock the rear wheels. If you choose to jack up the front of the vehicle, use jack stands for safety.

2. Initial Fill

Locate the power steering fluid reservoir. Clean the area around the cap to prevent debris from entering the system. Remove the cap and fill the reservoir to the "MAX" or "FULL" line. Don't overfill it.

3. Bleeding the System (Engine Off)

This is the crucial step. With the engine off, slowly turn the steering wheel from lock to lock (full left to full right) several times. This process forces the pump to circulate the fluid and helps push air out of the system. As you turn the wheel, observe the fluid level in the reservoir. It will likely drop as air is purged. Continue adding fluid as needed to maintain the level between the "MIN" and "MAX" lines. Listen carefully for any gurgling or bubbling sounds coming from the reservoir; these are signs of air being expelled.

4. Bleeding the System (Engine On)

After completing the engine-off bleeding, start the engine. Let it idle. Again, slowly turn the steering wheel from lock to lock, pausing briefly at each extreme. Do not hold the steering wheel at full lock for extended periods, as this can put excessive strain on the power steering pump. Monitor the fluid level in the reservoir and add fluid as needed. Continue this process for several minutes, checking for any signs of leaks or unusual noises.

5. Final Check and Adjustment

Once you've bled the system, shut off the engine. Allow the fluid to settle for a few minutes. Recheck the fluid level one last time and adjust as necessary. Inspect all hoses and connections for leaks. If you find any leaks, address them immediately.

6. Test Drive

Take the vehicle for a short test drive, paying close attention to the steering feel. The steering should be smooth and responsive, without any hesitation or excessive effort required. If you still experience issues like heavy steering, noise, or vibration, repeat the bleeding process or consult a professional mechanic.

Common Issues and Maintenance Concerns

• Low Power Steering Fluid: A common cause of power steering issues. Check the fluid level regularly and top off as needed. Persistent low fluid levels usually indicate a leak.
• Power Steering Fluid Leaks: Inspect hoses, connections, the pump, and the steering gear for leaks. Leaks can lead to fluid loss, air entering the system, and eventual pump failure.
• Worn or Damaged Hoses: Hoses can deteriorate over time, becoming brittle and prone to leaks. Replace worn or damaged hoses promptly.
• Power Steering Pump Failure: A failing pump will often produce whining or groaning noises, especially when turning the steering wheel. It may also result in heavy or inconsistent steering.
• Contaminated Power Steering Fluid: Dirty or contaminated fluid can damage the pump and other components. Follow the manufacturer's recommended fluid change intervals.
• Air in the System: This is why proper bleeding is so important. Air can cause noise, vibration, and poor steering response.

Regular maintenance, including checking fluid levels, inspecting hoses, and replacing the fluid according to the manufacturer's recommendations, can help prevent many of these issues.

Do's and Don'ts / Best Practices

Do's:

• Use the Correct Fluid: Always use the power steering fluid specified in your Altima's owner's manual. Different fluids have different properties and using the wrong one can damage the system.
• Cleanliness is Key: Keep the area around the reservoir clean to prevent contaminants from entering the system.
• Slow and Steady: When bleeding the system, turn the steering wheel slowly and deliberately. Rushing the process can trap air and make bleeding more difficult.
• Inspect Regularly: Inspect the power steering system regularly for leaks, worn hoses, and other signs of damage.
• Listen Carefully: Pay attention to any unusual noises coming from the power steering system, such as whining, groaning, or bubbling. These noises can indicate underlying problems.

Don'ts:

• Overfill the Reservoir: Overfilling the reservoir can cause fluid to overflow and potentially damage other components.
• Hold the Steering Wheel at Full Lock: Holding the steering wheel at full lock for extended periods can put excessive strain on the power steering pump.
• Ignore Leaks: Address any leaks promptly to prevent fluid loss and potential pump failure.
• Use Generic Fluids: Avoid using generic or "universal" power steering fluids, as they may not be compatible with your Altima's system.
• Forget Safety: Remember to wear safety glasses and gloves when working with power steering fluid.

Conclusion

Properly pressurizing the power steering system on your Nissan Altima is a crucial step after any maintenance that involves opening the system. By following the steps outlined in this guide, you can ensure smooth and responsive steering, prolong the life of your power steering components, and avoid costly repairs. While this guide provides a comprehensive overview, remember that safety and proper technique are paramount. If you are uncomfortable performing this procedure yourself, or if you encounter any difficulties, it's always best to consult a qualified mechanic. Keeping your Altima's power steering system well-maintained will contribute significantly to your driving comfort and safety.