Maybe the flywheel was warped? I’ve seen it happen on cars less than a few years old. The GTI while still a 3 cylinder didn’t ever feel bouncy when ticking over and never any issues with the oil. Tbh, I got it as it was more of a hot hatch and I couldn’t believe how gutless the engine was on most of the other super mini options. Might be a compromise if your used to your Merc
Here’s VW’s official stance on it….
Rattling noise from engine bay at idle vehicles fitted with 02S 5 speed manual gearbox (UK TPI) Release date: 05-Dec-2012 Technical product information Transaction No.: 2032109/1
Customer statement / workshop findings
Rattling noise from the engine bay area with the engine running at idle.
Technical background
Neutral gear rollover noise describes the condition whereby a rattling noise from the constant mesh gearing in the transmission is heard while the engine idles with the clutch engaged (pedal released).
It is caused by engine torsional vibration and is particularly prevalent on vehicles with a single mass flywheel and low idle speed requirements. The intensity of neutral gear rollover noise will increase with transmission temperature and / or an increase of torque loading, for example air conditioning or heated rear window activation.
The rollover noise is inherent to transmission design and will disappear when a gear is selected and the vehicle is driven. The noise is not detrimental to the transmission or engine components and does not constitute a manufacturing defect.
Production change
None.
Measure
When evaluating transmission complaints please draw on the statements above when assessing the complaint, remembering to account for engine refinement, gear selection ""feel""�, and clutch operation.
Warranty accounting instructions
Normal warranty guidelines apply.
Parts information
No parts information.
Customer information
Neutral gear rollover noise will not negatively affect the longevity or performance of the vehicle. It is concept related and does not constitute a manufacturing defect.
So, it’s not a manufacturing defect, just a poor design, when I say poor, maybe I should say cheap!