Quick answer: Bank 2 is running lean specifically at idle rather than across the whole operating range.
Drivers also search this fault as system too lean at idle bank 2, bank 2 lean at idle, idle lean bank 2.
P2189 is the Bank 2 counterpart to P2187. It points toward an idle-heavy lean condition, which usually makes bank-specific vacuum leaks, PCV routing issues, intake gasket problems, or low-load airflow errors more likely than simple fuel-pressure loss alone. Comparing Bank 1 and Bank 2 at idle is what makes this code useful: the bank split often helps you localize the air leak or sensor story faster.
P2189 often allows short-term driving, but rough idle, stalling, or repeated hard starts are enough reason to diagnose it soon.
Cause phrases often tied to this code: bank 2 vacuum leak, PCV leak, intake gasket bank 2, unmetered air at idle, MAF bias.
Brand hubs help broaden internal linking now and can evolve into make-specific diagnostic notes later.
Useful when the driver knows the wording but not the exact DTC yet.
Yes. Both describe idle-specific lean conditions, but on different banks.
Yes. A bank-specific intake leak is a classic reason for Bank 2 lean-at-idle faults.
Because the bank split can help you localize the leak, sensor, or manifold problem instead of treating the whole engine as one system.