W203 Mercedes Benz power steering

[Tedswagon]

Hi all,

My daily is a 2005 C350 estate. Good all rounder, ok, mpg is not too hot but in 10000miles mostly city driving and hard out of city driving it has managed 23mpg average. Not too bad for a 13 year old v6 3.5 petrol.

Problem is my power steering went before Christmas. Light to turn left and heavy to turn right. Most likely source was a PAS pump I thought. Fluids all look good so ordered a pump and replaced it and the belt.

For a week of town driving the steering was lighter than had been before but assumed it must have been heavier as the pump was on the way out. Second week after fitting (and since) . . . Steering is heavy as if there was no PAS at all. This changes form time to time it's heavy then it's really heavy. Slight vibration when parked and you turn the wheel an inch or so, but this is intermittent. I've checked fluids and cap off turned full lock to lock but no change.

If the pipes were leaking I'd see drops on car parking space, and notice loss of fluid.

I'm thinking maybe it's the rack!! Any thoughts??

Current mileage is about 90k odd.