when the rack goes out the wheels will be going straight, but the steering wheel will be slightly turned one way or another. What you problem sounds like to me is either T-rods or the lower ball joints. You can check the T-rods visually, just see if thay are leaking fluid. The ball joints you hafta check with the front wheels off the ground. Jack the front end up and see if you can wiggle the wheel against the lower controll arm. If so its probally the lower ball joint.