ive had a strange problem appear, at slow speeds when steering the car almost studs itself, if that makes sense, it almost feels like a flat tyre situation, now ive check the power steering fluid and the tyres, everythings fine, but this problm which doesnt happen all the time wont go away, somtimes its difficult to atually turn the wheel.

any ideas?

recent info

wheels need re weighting
wheel bearing needs doing
air con unit removed for replacement.

its worse when the car is from start up cold.