2002 Xtype cold start only - "gurgle" noise from air intake

[Xtype2002]

Ive recently purchased a 2002 Xtype 2.0lt with 89,000 original klms. Its a great clean car, looks to have been very well looked after, dealer service history etc.

The engine air intake has an odd gurgle noise which only occurs on cold start, is intermittent during this short period, dissapears when you lift the engine rpm just above idle.

When first starting and the engine idle is high, it doesn't appear until after a few moments when the idle speed settles back to standard - around 750rpm.

Ive changed the spark plugs (NGK Platinum, new coil packs - NGK, ive checked for air leaks around the manifold balance chambers and other air lines and connectors - cannot seem to find any. (I did NOT remove the air intake manifold for this job, the noise was there before i completed this task)

The noise dissapears when engine operating temp is reached, it gradually dissapears during warm-up.

Otherwise the car drives great, plenty of power runs smooth idels smooth.

If anyone could shed some light on this it would be very much apreciated. Ive included a short video of the noise to demonstrate.

Edited December 28, 2023 by Xtype2002
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