Ok guys, VAG-COM logs reveal no increase or decrease in performance and no fault codes with the N249 bypassed. Dump reaction is much quicker and throttle response seems improved.
I make no apologies for the "dirtiness" of my engine bay. Its there to propel the car, not to look all pretty.
On the AUQ engined Leon 1.8T Cupra and Sport, it should look something like this:
Here's a labelled diagram that is pretty self explanatory:
1. Remove the vacuum hose between the Fuel Pressure Regulator (FPR) and the underside of the intake manifold.
2. Use 4mm silicone vacuum hose and go direct from newly freed Vac port on intake manifold to top of DV.
3. Put a 6mm BRASS T-piece in the new hose parallel to the FPR and run another length of hose to the FPR vacuum port.
4. Cable Tie the new vac hose wherever it connects to something else.
5. Remove the Vacuum resevoir (Ugly black plastic thing directly over the No.4 cylinder coil pack). The hose going into it simply pulls off.
6. Plug the Vac Resevoir hose with a bolt and clamp it in there with a worm drive or jubilee clip. Do the same with the hose that used to be connected to the top of the Dump valve.
I recommend using brass t-pieces as they don't go brittle and snap when exposed to heat and oil, plastic does. Use cable ties rather than jubilee clips on the silicone hose you've fitted.
I hope this is a
help to Leon Cupra owners who haven't seen the need to fit an LCR intake manifold.