Tahoe Steering Noise

I have a 2000 tahoe with 80K miles...anytime the wheel is turned to the right I get the hissing noise from the pwr steering like you get when it is turned all the way . Turning it to the left makes no noise...Any Idea? it started when I was checking the ABS sensor on the left front . As a result of pulling the sensor the ABS light is now on , I have a new sensor on order . Does anyone have any ideas about the power steering noise?
Can the left ABS sensor and Steering noise be related in any way? thanks for your ideas

Mine hisses all the time in both directions whenever the power steering is activated (so basically any time I move the wheel). Has been doing so for about 10k miles now with no problems other than bad EVO sensor. I always just attributed it to additional strain on the power steering from putting on oversize (35") tires, 6" Fabtech lift, and/or the 3" body lift, which, by changing the height of the firewall relative to underhood components, could also change the sound dampening properties of the firewall(?) At least that's how I rationalize some of the strange sounds I hear.