How to Remove Air From Power Steering

Power steering
Can you even imagine driving without power steering? Barrett-Jackson/Getty Images

If steering your car becoming noisier and more difficult, it may be a problem with your power steering [source: Mobil]. The problem may simply be an air pocket that's trapped in the power steering pump.

The power steering pump operates by hydraulics, and anything that operates by hydraulics can easily be affected if air gets into the system. Any air that gets into the power-steering system will be compressed by the pump and will result in noise and difficulty steering.


The newer your car, the more likely it is that the manufacturer has a particular way that it recommends for bleeding the system. Be sure to check the owner's manual for guidance specific to your vehicle [source: Axle Addict]. But in general, here's how to remove the air from your power-steering pump.

  1. Make sure the engine is off and cool.
  2. Remove the power steering reservoir cap and check the power steering fluid level.
  3. Add as much fluid as needed to fill it up.
  4. Replace the cap.
  5. Locate the power steering bleed valve on the steering box. If you have difficulty finding it, just follow the high pressure line from the power steering pump to the other end, which will be in the power steering box.
  6. Push a hose on the end of the bleeding valve. The hose should be long enough to reach outside the front of the car.
  7. Place a drain pan on the floor in front of the car and place the other end of the hose into it.
  8. Turn on the engine.
  9. Loosen the bleed valve slightly.
  10. Turn the steering wheel to the right and left, from lock to lock, as much as you can.
  11. Shut off the engine.
  12. Close the bleed valve.
  13. Add power steering fluid to the reservoir until it's full.
  14. Check the fluid that came out into the drain pan. If you notice air bubbles, repeat the procedure.

You must repeat the procedure until the fluid in the pan is bubble free. When there are no bubbles in the fluid, you know the system is bled [source: Axle Addict].


Remove Air From Power Steering FAQ

Why is my power steering fluid bubbling?
If there are bubbles in the fluid, there might be a dangerous leak. These sounds usually mean your steering pump is worn out.
How do I know if I have air in my power steering?
If grunting noises come from under the hood - especially if they get louder while steering - you may have air in the system.
Is power steering equipped to self-bleed?
Power steering systems that have turn-top tubes sitting on top of the gear self-bleed while steering.
What if I don't bleed my power steering?
Delaying this can lead to harder steering, premature pump failure or a noisy pump. It is not advisable to drive the car before this issue has been resolved.
How can I bleed my power steering pump manually?
Open the bleed valve; turn the wheel from side to side multiple times; add some power steering fluid after the air has bled out; turn the wheel a couple more times and observe fluid levels again prior to driving