My 2001 Mazda Millenia steering started to pulsate when turing the wheel. It's more noticable on colder days. When I say colder I mean in the 50's (south fl). After the engine warms up steering feels normal again. I do hear a slight nock noise comming from the front of the engine when I turn the wheel. I replaced all of the fluid in the steering system to see if this would help any but it's just getting worse. Do you think it's time for a new power steering pump? The car only has 60k miles.