daveyboy1967

I think we can definitely say my EGR valve has been deleted, and it's so obvious now that it's funny. I've been intending for quite a while to try to find a missing fixing trim for my engine cover as shown below.
 
 

However it now turns out that what I was missing was an EGR valve!
 

 
Taxi for Dave please!

This may be the one you need?
FRONT LEFT DOOR LOCK ACTUATOR MECHANISM FOR AUDI A3 8P, A6 C6, A8 4E 8E2837015AA | eBay

Sorry mate, forgot to update this. Yes, the front actuator sorted the issues I was having with the front NS and as it was so cheap and a straightforward job I've got one for the rear NS too (not fitted yet) in the hope of sorting out a couple of issues with the rear interior lighting and an intermittent fault with the auto locking when you hit 15mph or so. I'll let you know if that solves it once I've fitted it.

I got some on Amazon that work fine, admittedly my car's a 2003 model so it may not be as fussy as newer models but I just had a quick look and these seem to fit the bill
GBrite - 2x Bax9s 8 smd led reverse bulbs for Audi A3 S3 RS3 8v Xenon White Canbus Error Free : Amazon.co.uk: Automotive
Only a tenner so worth a punt I reckon. I hate dim reversing lights too.

Problem solved, to cut a long story short I bought a similar Audi motor/linkage assembly, swapped the motors over, and did some judicious grinding on one of the linkages to achieve the desired throw on the wiper arms. More of a faff than it should've been but I got there in the end. If anyone has the same problem finding this particular linkage (8P2955023G) feel free to drop me a line and I'll be happy to explain in more detail, and thanks for everyone who offered help.