L322 heavy steering

has anyone had the fololwing problem or can advise me on it??

the steering on my 54 plate td6 vouge has gone really heavy, when i turn of the engine and start it back up it go's back to normal for a few seconds (nice and light) and then heavy again...

if any one can help me it would be really appreciated...

I had a similar issue on an 06 TD6. Was told by the main dealer that there was a "service advisory" on it due to a faulty sensor in the steering column. Took it back to the dealer I had just bought it from 1 week prior & they allegedly fixed it, but I still think its heavy.

I've just bought a 54 plate 4.4 with a similar problem so would love to hear of any solutions! Someone mentioned it might be something to to with the servotronic not sensing the speed right and firming it up but not sure how true that is.

Mike