FYI...
Throttle Body Gasket for 1.4 BBY (and I would assume it's the same for the other 1.4 engines too):
W036 133 161 C N/STK GASKET £3.60 inc. vat (price: 21/04/2017 from an Audi dealer)
I'd avoid ebay sellers, as they're literally doubling the price.
Edit: 27/04/2012
Have completed the throttle body clean yesterday and found that the above guide is missing some pretty useful and crucial information that could help people do this much more easily.
1. After you have undone the torx screw holding the air inlet (large black plastic tube) as well as the pipe clamp (on the left hand side as you look at it - goes to the air filter) and are then trying to undo the jubilee clip, you are meant to simply "pull it off the throttle body"... well, that's easier said than done because there are other fixtures holding it in place! Behind the "black plastic tube" air intake, there are two lugs. These are rubber mounted and are basically two plastic pins (fixed to the car) that go through two rubber grommets. It is MUCH easier when pulling up on the pipe going onto the throttle body to try to pull these up at the same time. You need to put quite a bit of force into it, but it does come off with a pop. When refitting them, simply push down as hard as you can, and they'll pop back on.
2. It is worth mentioning the orientation of the jubilee clip that goes over the pipe onto the throttle body is a pain to get to if it is oriented the wrong way round. If the screw is on the left hand side of the throttle body, it is very difficult to get to. Once you have removed it, I strongly suggest turning it around, which means it is far more easily accessible from the back. If you imagine it; as you look at the throttle body, the screw for the jubilee clip should be on the right. MUCH easier for next time!
3. It's all very well cleaning the throttle body with butterfly itself, but what about the bit that it attaches to?! Stuff a piece of throwaway rag into the hole and clean the area the throttle body attaches to just at thoroughly as you have on the other part. In some ways, this is almost more important as there are a couple of little tubes that go off in a couple of directions, which, if clogged up, won't help the running either. Mine was just as bad, if not worse than the throttle body itself. A much better tip, is to use carburettor cleaner rather than acetone - and wear goggles as most carb cleaners have powerful aerosols (more powerful than you'd expect). Don't forget to remove the scrap of rag from the hole when you're finished, with luck when you pull it out, you will drag out any rubbish that fell in while cleaning.
4. The modern and current throttle body gasket is metal (not card type). It's worth putting a little oil or similar over the surface to ease the fit. These are also a once only use gasket as there is a flange that is compressed upon tightening. So NEVER reuse the same gasket. For the sake of a couple of pounds, change it.
5. I disagree with Jupis' comment about using hex and screwdriver rather than an allen key. Space is very tight, and having read that comment I tried (in vain) with several different allen key sockets and screwdriver extensions and universal joints etc. In the end, I used an allen key and it was much easier (though still tight for space obviously)!
6. Be aware that when you remove the black plastic tube thing, you may dislodge wiring clips, they usually just push together but it's worthwhile checking just in case. They were put there for a reason after all!
7. If you read through the above, you'd be forgiven for becoming a little confused about what and how to do it with VAGCOM as there are apparently steps missing from the original version and then there are references to use the steps from Ross-Tech but if you go to their link, there are several different instructions for different engines. This is the defnitive one for 1.4 Audi A2s:
Procedure for performing a Throttle Body (TB) Alignment on DBW Cars using KWP-1281:
(Check to see if the engine speaks KWP-1281 by looking in the top left of the Open Controller Screen Some examples of KWP-1281 engine controllers are 2000+ Golf/GTI/Jetta/New Beetle/Audit TT 1.8T)
1. Plug in the VAGCOM OBD2 cable, and turn the key on (ignition 1) but do not start the car.
In VAGCOM:
2. [Select]
3. [01 - Engine]
4. [Measuring Blocks - 08]
5. (Type) 060 into the first 'Group' box
6. [Go!]
7a. [Switch to basic settings]
7b. Once you do this you will see the top right display (column 4) say ADP RUN. The TB adaptation is being done as soon as you press 'switch to basic settings'. You will see the values (in the first three columns) change and hear the TB cycle for the first few seconds then it will stop.
7c. Leave it in Basic Settings for about 30 seconds. (And until the 4th column says ADP OK)
8. [Switch to Meas. Blocks] button and you're all set.
Be sure not to touch the accelerator and make sure the engine is NOT running when you do this!
9. Turn off the ignition, remove VAGCOM cable etc. and wait 30 seconds.
10. Start car.
N.B. I use VAGCOM 409.1-S but I believe the procedure to be the same in all VAGCOM versions.