High revs at idle

[V1DL3R]

Hi All, my M12 has developed a fault where it will stick on 2,000 revs when I slow down to idle. If I try to stall the car it will go back to 1,000 and stays there. Lambda sensor maybe?

[AMG Merc]

Air leak?

[V1DL3R]

Interesting thought. It's weird though how I can make it drop back down though. So if I clutch in cruise to a stop from maybe 3000rpm. The idle will come down slowly and sit on 2000rpm. I then have to put it in third, start to pull away and let the engine strain to below 1400rpm and it will then sit on 1000rpm. The boost pressure on the gauge is reading correctly. Any suggestions as to where the leak could be which would create those symptoms?

[AMG Merc]

The rubber elbow pipe - connects vac pipe to manifold (located near throttle body), can disconnect without even showing so. Check it's not pushed on too as is do it can block the airflow.

[V1DL3R]

Thanks Rob! Does anyone have a picture of this before I get back on Friday just to make sure I am looking at the right area?

Thanks in advance.