Over the past few weeks in my '03 CL-S with 140K I have noticed the PS pump getting noisier and noisier. It does the typical whine that gets louder as RPMs increase and when the wheel is turned. I put a new pump on it today and also changed both soft rubber hoses that go to the reservoir. The whine is still there and the fluid in the reservoir looks like a tornado. I have bled and bled and bled it, but there is always a thin layer of "bubble foam" on top when I shut it off. The fluid level doesn't go down so I know that I am not leaking any fluid and fluid is not taking the place of the air in the system either. I think that a steady supply of air is somehow getting into the system. Looking at a parts diagram online, it looks like there are 2 O-rings in the whole system - 1 on the pressure switch and the other on the pressure hose where it meets the pump. Of course the new pump didn't come with a new O-ring so I had to re-use the old one. I'm going to order 2 new O-rings tonight and hope that fixes the problem. Anyone else had a problem with continuous air in the system?

 

You have a leak

 

sucking air on the inlet side, imho replace O-rings and see if issue goes away

 

I was thinking that too, just didn't expect it to be that way after putting in a new PS pump. Going to order a PS pump rebuild kit tonight and see if it fixes the problem. I cut the PS belt off with a pair of scissors this morning. Turning the wheel sucks now but at least the pump isn't screaming at me anymore.

 

Where exactly are the o-rings and seals located? The fluid in my car's reservoir looks like the water in a washing machine but there's no noise.

 

I linked to the wrong o-ring in post #6.
Here's the correct o-ring, which is part of the PS pump assembly: 91345-RDA-A01
Part #17:
https://www.acurapartsdiscount.com/o...QtYXV0b21hdGlj