2003 Impala 3.4L Was trying to solve a whine in steering system so replaced pump. Bled system of air with engine off. Still whines but not as loudly. Tried bleeding with engine on. Still whines. Tried bleeding with Mityvac. Still whines. Buzz might be a better word. Took a 10 minute drive. When I returned, there was about 4 oz of ps fluid on the ground below steering column. It appears to have leaked from the large black bell-shaped boot which is right above the rack on the column. I had to push part of this cover back down over the lip that the rest of the boot was gripping. Took another drive for 40 minutes, many turns, up to 60mph. No leaks this time. Did I break some seal or is there some pressure relief valve under that cover? Have since driven another 300 miles with no leak.