The car is a 90 Acura Integra LS. The problem is this when at idle and I have to turn the wheels left or right, near to the end of the turn of the wheel, to get out of a parking space the powersteering pump makes a loud squeal and the wheel seems like it's fighting me. This is only at lower RPM's, because if I rev it to say 2500 and turn the wheel it won't squeal. I've changed the belt recently (original belt on 130,000K) and also I've checked the level (also I put some non-Honda fluid in the system, a no no I'm sure) and the level is fine. Also I've turned the wheel while looking at the pump and the pulley locks up when the squeal happens. The rack is also leaking a little on the passenger side boot. My question is that is this either A) too tight belt B) fluid needs to be flushed C) bad pump D) bad rack?

PS: I know because of the leak I need to go and change the rack but I want to make sure this is the only problem before I do