my power steering pump is making noise when i turn at slow speed,should i flush the system or replace the pump? it is one a 2006 impreza.

Is it when you're stopped and just turning the wheel, or going less then 15 mph and turning?

Newer models have problems with an o-ring on the return fitting to the pump letting air in. The air makes it whine.

New o-ring fixes it.

Check your belt's tension. Loose belt can result in that noise & vibrations as well.

it is when i drive slow and turn. where do i get this o-ring at.

Dealer should have it.

 

If you remove the old one Napa might be able to match it up.

i will change the o-ring next week and then flush it out. the dealer changed the front pully  and changed the belts. the pully had seperated  and tore up the belts,thank God for warrentys.

now it squeals when i first start it. the belt seems tight and it goes away when i turn the wheel a couple of times. it turns ok it just makes a god awful noise when i first start it up and it gets funny looks from people. later this afternoon i will take the belt off and check the pump by hand,then check the belt for rips. do modern belts stretch,i know the old ones do.

now it squeals when i first start it. the belt seems tight and it goes away when i turn the wheel a couple of times. it turns ok it just makes a god awful noise when i first start it up and it gets funny looks from people. later this afternoon i will take the belt off and check the pump by hand,then check the belt for rips. do modern belts stretch,i know the old ones do.

Belt should not squeal upon start up. Check that belt for looseness. Belts generally don't stretch, but a cheapie belt will stretch. Cheapie belts, I bought from Autozone would stretch, but would not break. Learned my lesson to buy most expensive belt, no matter what brand name the belt is.

My '08 Outback has 70,000 miles.  I recently had all belts replaced, thinking it would be good preventive maintenance.  Since then, many issues with power steering pump.  It appears the shop that did the work did not understand Subaru's as well as they said they did, caused air to get into the system . . . and did not bleed the system properly. 

 

After several trips to the dealer, over several months, there was some improvement.  I decided the pump was now trashed and a new one was needed to get the issue resolved.  The new pump quieted things down significantly.  Car is scheduled for a follow-up visit this coming Tuesday, for further power system bleeding.  Current symptoms include a low level whine, going up and down with engine RPM . . . plus an intermittent howl.

 

All Wheel Drive Auto has an interesting blog on the o-ring-induced noise problem.  https://allwheeldriveauto.com/why-is-the-power-steering-making-noise-on-my-subaru-outback/.  If the o-ring is in bad shape and/or the hose connection to the pump (around the o-ring) has insufficient slack, air will get into system around the o-ring.  The bleeding procedure is not straightforward.

The pumps on these are "self bleeding".

You fill em up, start the engine and turn the wheels back and forth a couple times. The air pushes out into the reservoir on its own.

If that O-ring wasn't replaced, that will allow air into the system and will create a constant whine no matter what you do.

 

There are also other sources for accessory whining, and timing components can also cause a whining noise when they start to get old. What engine do you have?

the car will run briefly with the accessory belts off. remove them one ata a time, might help pin down a/c compressor or ????

Edited April 10, 20169 yr by 1 Lucky Texan

Engine is 4 cylinder.  Transmission is automatic. Car has 70,000 miles.  All scheduled maintenance has been done, since new.

 

When the noise first began (after timing a/c and p/s belts and pulleys were replaced by the non-dealer shop), I read blogs that said turning wheel back and forth several times would bleed power steering system.  I did that many times, with no benefit.

 

I then read that the belt shroud mounting bracket had to be configured with slack around the bolt into power steering pump, or movement of the engine would cock the o-ring and  perpetually cause air to get in around the o-ring.  I checked that mounting. The shop that did the initial belt replacement had configured it rigidly.

 

I had the Subaru dealer re-do the belt and pulley replacement (except timing belt), and replace the o-ring.  After that work the mounting bracket had the requisite slack.

 

The worst of the noise was gone, but some remained.  After a few more months of the noise, with a follow-up to the dealer, I decided the pump was now ruined.  I had a brand new (not rebuilt) pump installed by the dealer.  All noise stopped.  This made me think all other accessories were be in sound condition and I was good to go.

 

A couple days later I began hearing a low level whine, constant level, pitch increasing and decreasing with engine rpm.  I initially thought this to be a new issue . . . that a bearing in alternator or a/c compressor was failing.  Then a periodic howling began, such as I had heard before the pump replacement.  The howling had stopped for a while after the pump replacement.  I once again suspect the power steering system to be source of all noise.

 

Sooberoo, you mention that "timing components" can cause a whine.  To which components do you refer?

can you or your mechanic get you eye close to the top of the open PS fluid tank You need to look for foam/bubbles while idling - maybe as someone works the wheel back and forth.

 

example;

There are no bubbles in the p/s reservoir.

 

Sooberoo, you mention that "timing components" can cause a whine.  To which components do you refer?