The car sat a few days, Then when started there were a thump, thump, about 6, and the front end eased up slightly.
Is this a portend of problems? No warning lights at all, or any other indication.

 

Was the Jag moving or had just stopped moving at the time that you heard the noise?

 

Just on start up, It seems the longer it sits, the more the compressor works.
Yesterday only two thuds. Drove it 1000miles, but every day, and no compressor sounds.

 

Seems you have a very small air bag leak if you dont habe any warnings.
The air bag shocks can be replaced easily.
I had the same issue that lasted well over a year before it got bad enought for me to replace.

 

Where can I get them, & can any garage do it? With Thanks David

 

Arnotts. I bought from this company & had some pot on my car a couple months ago...

Look at this on eBay http://www.ebay.com/itm/371006570144

 

Yes, I've heard of the name. In red writing, "they don't ship to Canada"!

Would these be adjustable, to lower the front end?

 

Keep in mind that Arnott no longer rebuilds or offers direct replacement of the OEM shocks. The current Arnott models do not support the ECATS function.

If you want to keep the ECATS function, you should either buy the OEM Bilstein units or a rebuilt unit of the originals.

 

From what I've read in the forum, to rid the car of the air shocks for the front end is the best route to take?