I had this issue happen for the first time today on 2018 GLC43 with 55K miles. All service is up to date except spark plugs which I think are either at 50K or 60K.
The engine misfired from cylinder 2 upon cold start with codes P0300 and P0302. Check engine light is on.
There is a ticking noise which sounds pretty loud (?) to me, as well as an intermittent 'whooshing' sound coming from the passenger side of the engine.
I've recorded ~20 s of the engine running (when hot) here:
AMG GLC43 engine ticking and vacuum leak?
Anybody have an idea of what this could be?
Thank you all!