Was out razzing down some lanes the other day and went over a humpback bridge quite quickly Once over I started to get a whine building up in intensity as I continued to drive. It followed engine revs when in neutral and once I'd stopped and popped the bonnet it seemed to be coming from the powersteering pump. If I reved the engine to 3k and moved the steering wheel the pump noise increased with each movement. After about 1 minute of idle the noise went away and has not yet returned.

Have I damaged the pump? Why did it do this? Surely all the fluid didn't leap about that much?! I have checked ALL fluid levels, which I'm glad to say are ok.

 

The negative G over the bump may have caused temporary fluid starvation to the power steering pump. Low fluid level can cause a similar noise.

Les