Noise fron engine bay when touching accelerator

[AudiA3B]

Hi guys, hopefully some one can help with my problem.

If I am using cruise control, when the selected speed is achieved the car obviously tries to hold that speed but while it's holding that speed there is some noise from the engine bay.

The steering wheel is vibrating while this noise is happening too but only slightly. The vibration stops when I accelerate and pick up speed.

It's almost like a light brake disc shield friction whirring noise but it's not.

I can make the car do the noise by just trying to maintain 30mph or 40mph etc . I guess it's a trip to the garage but anybody got any idea about what is causing the noise?

Some facts:

There is no noise under normal acceleration (only while trying to maintain a speed)
The engine idles, revs all fine. This noise only happens when the car is moving and trying to maintain a certain speed.
While it's making this noise, if I accelerate the noise stops
This happens at any speed really beyond 20mph
I can't hear any noise if the windows are closed.

2016 Audi A3 1.4TFSI Sline.

Thx

 

[Booti]

If you are feeling it through the steering wheel, the first thing I would check is the wheel nuts are tight.
I have had it before where a wheel was tighten but not torqued and I got a vibration exactly as described.

 

[callumw]

Less likely is that something like the steering rack is slightly loose.
That way under load the engine torque is holding the rack in place, but when under a static load the rack has a small amount of play in it.

I saw a video on it with an old Audi, but and it was easy to detect and correct (literally just tighten the correct bolt and it's fixed)