P2189

System Too Lean at Idle Bank 2

Q: Is it safe to drive with P2189?

Short term, yes, but a lean idle can cause stalling and rough running. Fix it before it leads to lean misfires or leaves you stalled at a stop.

Q: Can I just clear P2189?

It comes back once the ECM relearns a lean trim at idle; the leak, metering, or fuel-supply issue must be repaired.

Fuel & air metering Generic OBD-II Medium

What it means

P2189 means that at idle, bank 2 is running with too much air for the fuel supplied (a lean mixture) and the ECM has reached its correction limit. Because manifold vacuum is highest at idle, it's most often a vacuum or intake leak, though a dirty MAF sensor or low fuel delivery can also cause it.

Medium

Can I keep driving? Usually driveable, but a lean idle causes rough running and can lead to stalling or lean misfires, so address it before it worsens.

Real-world scan data

Seen in

113

scans in the past year

Found in

<0.1%

of scans

<0.1%

of scans that found faults

Appears alongside · share of P2189 scans

P2187in 77.9% of scans

P0174in 44.2% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Check-engine light on
Rough or unstable idle
Occasional stalling at idle or when coming to a stop
Hesitation off idle

Common causes

Most likely first

Vacuum or intake air leak on bank 2 (very common at idle when manifold vacuum is high)Likely
Faulty or contaminated mass air flow (MAF) sensorCommon
Incorrect or disconnected PCV hose routingCommon
Low fuel pressure or restricted/dirty injectorsLess often
Exhaust leak upstream of the O2 sensor, or a faulty front oxygen sensorLess often

How to diagnose & fix

Work through it in order

Read freeze-frame and fuel-trim data to confirm a lean condition at idle on bank 2.
Smoke-test the intake and vacuum system — small leaks show up most at idle; check the PCV hose.
Inspect and clean the MAF sensor and check the intake ducting for cracks or loose clamps.
Check fuel pressure and injector delivery against spec.
Inspect for exhaust leaks near the front O2 sensor; replace the O2 sensor only after leaks and metering are ruled out.

FAQ

Quick answers

Is it safe to drive with P2189?+

Short term, yes, but a lean idle can cause stalling and rough running. Fix it before it leads to lean misfires or leaves you stalled at a stop.

Can I just clear P2189?+

It comes back once the ECM relearns a lean trim at idle; the leak, metering, or fuel-supply issue must be repaired.

Read & clear P2189 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX