Ford Repair: Power Steering, power steering pump, vent hole

Question
Earlier this week my starter went out on my 2003 Ford Taurus (74,000 miles, V6). I replaced the starter,  but ever since then my power steering has been acting up. On the first day it turned fine but made a groaning sound while turning. The next day the steering started to get harder to turn especially at lower speeds. The fluid level is fine but it is foamy after driving and usually spits out the vent hole. Is this simply a bad power steering pump that needs to be replaced? And would me having turned the wheel multiple times while the engine was off to get it in the back of my trailer when it wouldn't start have any thing to do with it. Thanks for your time.

Answer
turning the steering when the vehicle is off will aerate the system. if you access to a suction type gun or pump, drain the resevoir of the fluid in it and add mercon v ( trani fluid to it ). while idling bring the rpm's up to about 1200 and turn the sterring wheel from lock to lock about 10 times. if this doesn't fix it- then replace the pump