As in the title really chaps, my first short project for 2017 is on the joys of replacing this failure prone part. Having found this part leaking on my old bus some months ago I have now decided it is time to sort it out, moreso because my coolant level is dropping faster than previously noticed so safe to assume if I don't do it asap it will just fail all together, and I don't fancy that . It has been stated in numerous sites etc that it is a well documented problem on the 2.0tfsi's but having spent a lot of time today there doesn't appear to be a great deal on the subject over here in the UK, but its very well documented in the states, with a lot of very helpfull threads etc on a few sites. Anyway, I thought I'd do a write up with my experience of the replacement just for us audi-sport users, well anyone really , just makes things a lot easier to find a thread than searching the whole wide web for hours and filtering out all the non relavant info. So having had a good old search and having compared all the assorted methods of replacement it would seem to be prudent to obtain the following parts first. you'll need the flange with the three O-rings , one is already fitted ( the engine block connection) , one small o-ring which is for the temp sender port and the third larger o-ring is for the heater quick connector fitting port. parts: 1,2,4,5,6 it is also a good idea to get a spare temp sender retaining clip , the two fixing bolts and the short section of rubber hose that attaches the flange to the metal tube section, none of these parts are really needed but since their cost is very cheap it is silly to not get them for the obvious reason below. (1) the original screws fitted may be difficult to remove or get lost. (2) The temp sender retaing clip may get damaged or dropped and lost. (3) the short rubber hose section can be a pain to get off , so quicker to just cut it off and replace rather than fight with it for ages. parts : 13 and maybe two new hose clips. It goes without saying you will need suitable tools to undo these screws and unclip parts etc in a confined space, what you use is personal choice , so what ever works for you. There seems to be a few differing approaches to the fix , some seem to be easier than others, from my research the prefered method is that to gain a much better view and easier access to the area the Brake vacum pump should be removed ( only 3 screws ) and does make things a lot easier especially when dealing with the bottom quick connect hose , and removing the two fixing screws. Just remove or loosen the parts around the bulkhead area that can be moved away or removed easily to make as much working space and access to the back of the block. Draining down the coolant enough or clamping the hoses , all down to personal choice. Rather than struggle with the small lenght of hose from the flange to the metal coolant tube and probably mess it up anyway, just cut and replace it with the new hose, many find it comes off easy other say it does'nt , based on a 10 year old car that has not had the hose disturbed before , easy removal may be far from the case, anyway , same applies take your choice. Another area to keep in mind is the lower hose connection or quick connector from the heater, inside the socket that clips onto the flange their is an o-ring , dont skimp , use the new one. It goes without saying that upon refitting the new flange etc , refitt anything you have removed and topup the cooling system. I think that just about covers the main task, based on individual methods used some things may not apply or parts may not be required, all down to the person doing the job really. So then chaps, I hope this guide is of some possible help to other owners afflicted by this problematic part. I am about to perform this same job shortly and will be using the same method , if i find any shortcuts and better suggestions i will update accordingly. I'll upload some decent pics aswell to go with this guide. Please note , this is only intended to be DIY guide and anyone using it should be aware of this and make sure you are fully conversant with what is involved before you embark on the task/job, so good luck. here are a few pics from other links as a starter in no special order, i'll be adding my own more indepth pics shortly when I commence my fix.