[kele]

An old thread this one; but nonetheless it gave me the confidence to have a go at changing my compressor and relay yesterday. It is a good write up from GlynC. But since this is a sticky, I add a few pointers that may help others:

1) My compressor cage had four star bit bolts (rather than three described by Glyn). Two nearest the wheel at the back, one nearest the engine and the dreaded one at the front - behind the bumper. I replaced the front one with a traditional hex headed bolt so it is easier to change "next time"!

2) Worth checking the power steering fluid level whilst you are down there. Mine needed topping up

3) I seemed to have even less room than described in Glyn's post. I would recommend taking the N/s airbox out completely to give more access and visibility. I was able to take the front bumper off on one side only. That is unavoidable unfortunately.

4) Once the cage was out and on the work bench, I found one of the three steel bolts that secures the compressor to the cage was corroded to the aluminium cage and also the spacer. Hence it sheared when taking it out and I had to drill it out. A pain because the other two were fine and reusable. The Air Compressor Mounting Kit is part number 4Z7698505 and currently available from our sponsor.

5) By comparison, changing the relay was a walk in the park. Part number 4HO 951 253A (labelled 645) replaces the 8DO 951 253A (labelled 373).

5) Whilst my old compressor had not totally failed, it was only a matter of time. Just one heart stopping moment once the job was done; I had a amber suspension warning light and code "01437 - Control Position not Learned 005 - No or Incorrect Basic Setting / Adaptation". This code was not there when I started the job. To solve this I had to enter the distance between the wheel arch and the centre of each wheel. The procedure is described here

Not the easiest job I have taken on, but all running sweet now. Should be good for another seven and a half years..