Intake Manifold & Rear Washer Nozzle
2011 GTI w/ 45k. No Mods. New spark plugs @ 40k. Currently at the dealer for CEL and getting a new intake manifold.
No symptoms prior, or after CEL except a few rough starts but still very smooth. I had some odd acceleration hesitation in the lower band but so intermittent I didn't notice. Sometimes while stopped at a light it felt like the engine was randomly miss firing. Again, very minor and hardly noticeable, and more importantly no CEL. I thought it improved / went away with the spark plug change.
I assumed it was something simple. Checked the coils for creep. Nothing. Listened to the engine. Nothing. Still ran smooth on my trip home before I took it in for service the next day. Dealer said it was the intake manifold, I'll have to ask for the codes just in case. Replacing it under my VW warranty (which is extended, don't ask...).
CEL CODES: P1570, P2015, U0002, U0429
Only other issues: rear washer fluid dripped.