power steering?

I was looking at a 99 GA SE to purchase and it has a 3.1L V6 with 122K mi on it. Took it for a test drive and when I returned I popped the hood again to notice a small amount of fluid on top of the reservoir right next to the cap of the PS pump. The fluid was not there before I went on the test drive. Also when I removed the cap, it had pressure on it. This struck me as being odd as I have never seen a PS reservoir have pressure on it.

I am concerned about it. Should I be? Does it mean the pump is bad or going bad? Replacing it is not a problem, but I want to make sure it is not the rack that is going bad. Is there a way to tell? I did notice before I test drove it and had it running with the hood up, I could hear some noise, thinking that a pulley or pump was wearing out.

Any help would be appreciated.

Thanks

Chad

sounds like had air in system; introduced if system ran low on fluid, sucked in from deteriorating hose on low side or if parts replaced and not bled properly. worn pump will make noise. air in system will make noise and will cause pressure build up in reservoir.

have only seen rack leaks, hose leaks and noisy pumps on these cars.

Not a big concern but get it addressed before you by the car and have your mechanic inspect the car.

if there was air in the system, wouldnt you see bubbles in the reservoir?

I have same deal. Whenever I take off the PS cap, there's a little "psssst" of pressure release. I noticed that the cap is a pressure cap, with a spring on it that appears to be designed told hold in pressure up to some level before releasing. I never heard of power-steering systems running under pressure like this (seems similar to coolant system). Anybody know the reasons behind it? Why have a pressure cap on the PS-fluid reservior?

if there was air in the system, wouldnt you see bubbles in the reservoir?

yes. but not always. Some newer systems recommend running the system under vacuum for 5 to 10 min to remove air from the system; after pump replacement to quiet noise created from air in system.

I have same deal. Whenever I take off the PS cap, there's a little "psssst" of pressure release. I noticed that the cap is a pressure cap, with a spring on it that appears to be designed told hold in pressure up to some level before releasing. I never heard of power-steering systems running under pressure like this (seems similar to coolant system). Anybody know the reasons behind it? Why have a pressure cap on the PS-fluid reservior?

some systems can develop 1000psi on the high pressure side.

Was wondering if air compressed on the high side is decompressing in the reservoir and hense the pressure release when the cap is opened.