P2189
System Too Lean at Idle (Bank 2)
This code means the engine's computer has detected that the air-fuel mixture is too lean (too much air, not enough fuel) specifically when the engine is idling on the second bank of cylinders. This typically points to unmetered air entering the engine or an issue with fuel delivery.
System Too Lean at Idle (Bank 2)
Common causes
- high
Vacuum Leaks
Cracked or disconnected vacuum hoses, intake manifold gaskets, or PCV system components can allow unmetered air into the engine.
Typical part cost: $0-200 repair
- medium
Faulty PCV Valve/System
A stuck-open PCV valve or a leak in its hose can create a vacuum leak, especially at idle.
Typical part cost: $20-100 part
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First things to check
- 1Listen for vacuum leaks and visually inspect all vacuum hoses, intake manifold gaskets, and PCV system components.
- 2Perform a smoke test on the intake system to pinpoint vacuum leaks.
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Related codes
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Frequently asked questions
What is the difference between P2187 and P2189?
P2187 refers to a lean condition on Bank 1 (the side of the engine with cylinder #1), while P2189 refers to a lean condition on Bank 2 (the opposite side). If both appear, it often points to a common issue like a MAF sensor or a large vacuum leak.
Can a dirty air filter cause P2189?
A very dirty air filter can restrict airflow, potentially causing a rich condition, not typically a lean one. However, if the MAF sensor is dirty due to a poor filter, it could cause misreadings leading to a lean condition.
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