This has been happening for a long time now. After driving the car and switching the engine off, after about 15 seconds the front suspension will drop between 1 and 2 inches but it drops and stops at the recommended height of 493mm which means it is riding too high while driving.
I have fitted new front strut assemblies, because of a burst air bag, but it did it before this as well.
I can hear some air releasing under the right wheel arch when it does it but I presume this is the valve block letting air out the bags.
When connected to the IID tool the voltage traces move when I slightly move the height sensors.
All the front suspension components have been replaced.
So, can anyone come up with any suggestions as to why it is doing this?
Thanks Kev.
[ 2011 4.4 TDV8 ]

I assume you have recently done a calibration? Mine would readjust sometimes but since I replaced a height sensor that failed I haven't noticed it happening. When I took the sensor off the pivot was very stiff so I assumed it was suddenly jerking and sending a new height reading to the ECU rather than continualy adjusting. 2012 TDV8 Vogue (L322)

Yes, recent calibration and all the sensor points are free to move.
Just don't understand what's happening.
How can the bags be pumping up while driving.
I can only think there is something wrong with the sensors.
I think I'll uncouple the sensors and move them slowly to see if there are any voltage spikes.
What brand sensor did you use as I hear pattern ones arn't reliable?

Used OE for the one I replaced but bought pattern part front and rear to keep as spares in the boot incase another failed as learnt a valuable lesson that if a sensor fails it can leave you stranded. 2012 TDV8 Vogue (L322)