Golf MK7 Engine Noise

[stem]

The Car:
VW Golf R Line Edition (2016 pre-facelift)
1.4 TSI (Petrol)
Manual gearbox
18,000 miles

The Problem:
Very rapid fast tapping / drumming noise under gentle acceleration (reminds me a bit of the sound made by a woodpecker )
Stops as soon as the accelerator is released
It's louder with the window down
Only audible in the lower gears
Intermittent; does it for a while and then stops
Just started happening at about 17,000 miles
Engine is performing as normal, perfectly smooth and no loss of power

I'm a bit reluctant to take it to the dealer as I know it won't make a sound in their presence.

Thanks in advance for any assistance

 

[Burnerman]

Can you find out if your engine has a timing chain or a timing belt? The very latest cars are back to a belt but first things first!
John

 

[stem]

I believe that it is an EA211 engine and is fitted with a timing belt.

The engine has ACT and the noise comes when the accelerator is pressed and the '2-Cylinder Mode' display goes off at the same time. As I understand it, the operation of the ACT is via the camshaft. Don't know if that is significant or not.

 

[Burnerman]

No experience with this one I'm afraid but:
https://www.golfmk7.com/forums/showthread.php?t=31344
May be of interest!
John