These later model golfs do suffer with electronic throttle body faults.(there is no throttle cable).Part of the fix is to check the multi connector to the throttle housing as the wiring can be too tight and cause the connections to open up.hth

What engine is it?

You mentioned it was faulty in the morning but OK in the evening. This sounds moisture related (engine warmth dries out electrics during the day - damp at night).

How about coil pack or packs. Depending on the petrol model it will either have individual coil packs above each spark plug or a wasted spark coil pack (on the side of the engine with ignition leads feeding spark plugs). If its the former then you will keep dropping one cylinder. If the latter is failing it will keep dropping "two" cylinders as it made up of two coils each feeding two plugs. Both are common failures and "moist" conditions would make things much worse in either case (i.e. first thing in the morning). I had this happen on a Octavia 1.416v (same engine as Golf) and it threw up allsorts of misleading error codes when faulty.