[Too Cold NB1.8T]

OK:

1. There very well might be a bad valve somewhere, however, vacuum/pressure leaks can be extremely difficult to find and where this engine is concerned, the smallest vacuum/pressure leaks can cause crazy negative results.

The only true way to make sure that no leaks exist is with the use of a good smoke leak detection tool, believe me I know, some leaks I could find through common methods like spraying carb cleaner or using propane gas but even after weeks of searching, these methods left some leaks undiscovered, also, just because a clamp is tight does not mean that a leak is not present, sometimes an over tightened clamp can create a leak.

I finally did some intense research before purchasing the best system "Smoke Pro" had to offer and with-in five minutes of use it revealed three vacuum leaks, valve cover gasket, adjustment screw on my HKS SSQV (I have since upgraded to the new non-adjustable version) and an injector seal, it also located a leak where the turbo and exhaust manifold meet, the three bolts had backed out some.

The car ran like a Bat out of hell after I completed the repairs, it is an expensive tool but it is well worth the cost, it paid for itself after three uses and without the hassle of going around and around with some shop that "might" be of help but will charge hundreds of dollars in the process.

FYI, none of the above issues triggered a fault code either yet they caused the car to run a bit erratically, including surging under boost.