Suspension Problem

[MY95]

I have a knocking noise coming from the front passenger side of the car.
I can twist the turny bit in the photo on this side but not the other.
There sounds like theres a releasing of air when this problematic side is pushed down on.
New spring and shock absorber fitted only a few thousand miles ago.
Any ideas?

Photo of the bit I can twist:

[attachment=18472]

[Toms306]

The top nut is probably a bit loose if you can twist the metal spacer thing, that'll cause a knock over bumps.

A quick 'gushing' sound is normal as the oil/gas moves in the shock.