Hello , would you please help ? I have 2007 Mercedes R500 , the steering is fine when driving , but when I stop and move the car to park , making left , right , backup and park , the steering is so heavy , feel like no power steering at all ? What is the problem and how can I fix it? Thanks in advance

I would first jack up the front end off the ground and check to see if anything is binding near last few inches of steering travel .May save you time and money replacing parts.It costs nothing but a little time..