Daniel Forrester

I'm trying to diagnose a problem with the steering on my Zafira B 2012 1.7 CDTI A17DTJ and would appreciate some input on what is the likely cause. The steering feels heavier than it should and very slow to react, sloppy might be a word for it and it is quite unnerving to drive. The power steering appear to function to some extent but doesn't respond as expected. When the car is stationary and the steering wheel is turned it kicks back in the opposite direction at the point you stop turning the wheel. I've checked the battery, alternator and used the opcom tool to check the steering pump current and speed etc and all seems to fit within the expected values. I'm trying to work out whether the likely suspect is the power steering pump or steering rack or something else? Any ideas would be appreciated. Thanks Daniel