Having to replace the rack and pinion for the Second time

I have a 2001 lincoln ls, I having to replace the rack and pinion for the second time in a little over a year. Air is getting into the rack-pinion and the power steering pump. Does anyone have any idea why this is happening?

I have a 2001 lincoln ls, I having to replace the rack and pinion for the second time in a little over a year. Air is getting into the rack-pinion and the power steering pump. Does anyone have any idea why this is happening?

There must be a leak on the suction side of the pump, but how does that cause a total system failure?