Got this error code.. P2098 Post Catalyst Fuel Trim System Too Lean Bank 2

[Dawie #3]

Hi BMW fans.. Please guide me here

I have the following error code
P2098 Post Catalyst Fuel Trim System Too Lean Bank 2

In simple words what does it mean and do you have any ideas of how it can be fixed?

 

[Blue Shirt]

You may have a vacuum leak in the intake with unmetered air that enter the intake manifold, causing a lean fuel/air mixture.

It would help if you could tell us which engine is in the car?

 

[Dawie #3]

Apologies bmw e90 320i 2009 face-lift