I've noticed a few threads with this problem but no definitive answers so just wanted some clarification. My power steering makes a whining noise when i turn the wheel lasts about 3 seconds can also hear it at low revs when driving. Thought it was the fluids so got it drained and went out and bought the proper stuff from VX to go in, but still the same noise. I have noticed the steering seems to be slightly light at times, well different from when i first bought it.
The car is a Enjoy Astra Mk4 54 plate so is a electric pump, the lights slightly dim when i turn the wheel but i don't think that is related, and the only modification's i have done is a new head unit.