Hi ChrisP. - further to our telephone conversation. It is my understanding that your front levelling valve and your suspension pump have been "serviced' so to speak. I note your comments regarding "stirring up the fluid' in the reservoir, even though I find it difficult to comprehend that, and a "loud bang" after the car had been running for a matter of 'seconds' and then the suspension dropped again. Reiterating from the telephone call I would say that:
1. If there was a loud bang, chances are that the coupling between the back of the pump and the idler gear driven by the camshaft has been destroyed. It is just a loose fit connecting up the two driving and driven yokes.
2. Some sort of physical damage has been occasioned to the oil pump - if there was a loud bang, the pump would more than likely be destroyed.
3. There is very little to go wrong with the Pressure Regulator itself - there are no moving parts and it is difficult to substantiate replacement of the unit.
As suggested, please phone back after your next consultation with the Star Shop - I will endeavour to help you and advise as best as possible. I am also hoping for a call from our "Dear Doctor" in Kalamunda. Regards Styria