P2187 on a 2022 Toyota Camry
System Too Lean at Idle (Bank 1)
What does P2187 mean on a 2022 Toyota Camry?
P2187 is set when long-term fuel trim on Bank 1 goes excessively positive (typically beyond +20 %) specifically at idle, but stays closer to normal at part-throttle and cruise. The distinctive pattern — lean only at idle — almost always points at a vacuum leak rather than a fueling problem. At idle, intake manifold vacuum is at its highest, which amplifies the effect of any leak; off-idle, the leak path becomes a smaller fraction of total airflow and trims look fine.
Symptoms on a 2022 Toyota Camry
- Check Engine Light is illuminated
- Rough or unstable idle, especially when warm
- Possible hesitation or stumble immediately off-idle
- Stalling at idle (worst cases)
- Slight reduction in fuel economy
- May be paired with P0171 (general lean Bank 1) if the leak is large
- No drivability issue at cruise
Likely causes on a 2022 Toyota Camry
- Vacuum leak (intake gasket, brake-booster hose, PCV, throttle-body gasket) Most commonEstimated repair: $80– $600
P2187 is essentially "lean at idle = vacuum leak" until proven otherwise.
- Stuck-open EVAP purge valve introducing fuel vapor unmanaged CommonEstimated repair: $80– $300
- Cracked plastic intake manifold (Ford 4.6/5.4, Chrysler 4.0, GM 3.6) CommonEstimated repair: $250– $900
- Failing PCV valve or hose CommonEstimated repair: $30– $200
- Failed or biased Bank 1 upstream O2 sensor OccasionalEstimated repair: $150– $450
- Throttle body gasket leak OccasionalEstimated repair: $30– $200
- Carbon-coked throttle body letting blade hold slightly open OccasionalEstimated repair: $20– $200
How to diagnose this on a 2022 Toyota Camry
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Compare idle vs cruise fuel trims
Read Bank 1 LTFT at idle and at 2500 RPM cruise. P2187 with LTFT around +20 % at idle but near zero at cruise is the classic vacuum-leak signature. P2187 with high trim at all RPMs is a broader lean condition (likely P0171 alongside).
Tools: Scan tool with live PIDs
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Smoke-test the intake comprehensively
Pressurize the intake with smoke through the throttle body. Watch every gasket, hose, vacuum tee, the brake booster line, the PCV system, the EVAP purge line, and any unused vacuum ports. The leak path is somewhere in there.
Tools: EVAP / intake smoke machine, Flashlight and mirror
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Inspect the PCV system
The PCV system is a common P2187 cause — particularly the hose from the valve cover to the intake. Aged rubber cracks and PCV valves stick open. Pull the valve and shake — it should rattle. A non-rattling PCV is finished.
Tools: Common hand tools
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Disconnect the EVAP purge to test
With the engine warm and idling, disconnect the purge valve. If the rough idle smooths out and LTFT drops, the purge valve was stuck open. P2187 + idle improvement on purge disconnect = purge valve.
Tools: Hose disconnect tools
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Inspect the brake booster hose
A failing brake booster diaphragm or hose is the single most overlooked P2187 cause. Pull the brake-booster line off and cap the manifold port. If idle smooths out, the booster or its hose is the leak.
Tools: Hose plug or vacuum cap
Known Technical Service Bulletins for the 2020-2024 Toyota Camry
Manufacturers publish Technical Service Bulletins (TSBs) when a known issue affects a specific vehicle. These bulletins come from the NHTSA database for your Toyota Camry.
- ENGINE Feb 26, 2026
OBSOLETE NOTICE February 27, 2026: This bulletin is no longer applicable and is now obsolete.
NHTSA #11029896 - ELECTRICAL SYSTEM Jan 29, 2026
OBSOLETE NOTICE January 30, 2026: This bulletin is now obsolete. Please see T-SB-0001-26.
NHTSA #11028726 - ELECTRICAL SYSTEM Jan 27, 2026
Some 2018 – 2024 model year Toyota vehicles equipped with a Premium Audio with Dynamic Navigation System require a Special Service Tool (SST) USB flash drive to update the map, points of interest, and system software.
NHTSA #11028722 - UNKNOWN OR OTHER Jan 6, 2026
Some 2005 – 2026 Toyota vehicles that have undergone water intrusion may exhibit a condition in which a musty odor is present. Follow the procedures in this bulletin to remediate the odor and address this condition. The purpose of this Service Bulletin is to provide general guidelines and procedures for odor remediation. This Service Bulletin provides a guide on how to prepare and treat the interior of the vehicle for odor remediation. Refer to the applicable model and model year Repair Manual and the EPA (Environmental Protection Agency) website for the most up-to-date safety and precautionary guidelines.
NHTSA #11028712 - ENGINE Aug 6, 2025
The specific condition covered by this program is for a small engine coolant leak that can occur from the flow shut-off valve that can allow coolant to drip on other parts of the vehicle. This can cause "Engine Maintenance Required" to be displayed on the instrument cluster or cause the A/C not to function normally. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
NHTSA #11022949 - ELECTRICAL SYSTEM Jun 24, 2025
Some 2021 – 2022 model year Avalon, 2018 – 2024 Camry, 2019 – 2025 model year Corolla, 2022 – 2025 model year Corolla Cross, and 2019 – 2025 model year RAV4 vehicles with A25A-FKS and M20A-FKS engines may have a MIL ON condition with one or more of the following Diagnostic Trouble Codes (DTCs) upon cold soak start up with engine coolant temperatures between 14°F – 41°F: •P030027 – Random/Multiple Cylinder Misfire Detected (Emission) Signal Rate of Change Above Threshold •P030000 – Random/Multiple Cylinder Misfire Detected •P030100 – Cylinder 1 Misfire Detected •P030200 – Cylinder 2 Misfire Detected •P030300 – Cylinder 3 Misfire Detected •P030400 – Cylinder 4 Misfire Detected
NHTSA #11020670
+14 more TSBs available in MECH AI's TSB explorer for this vehicle.
Common fixes
- Repair vacuum leak(s) found by smoke test
- Replace the EVAP purge valve
- Replace cracked plastic intake manifold (model-specific)
- Replace the PCV valve and hose
- Repair brake booster vacuum leak
- Replace the upstream O2 sensor if biased
About the 2020-2024 Toyota Camry
The 2020-2024 Toyota Camry was commonly sold with the following powertrains: 2.5L I4, 3.5L V6, 2.5L Hybrid I4. Common trims include LE, SE, XLE, XSE.
Why “lean at idle but not at cruise” points at a vacuum leak
The size of any intake vacuum leak is fixed — say, 5 grams per minute of air. At idle, the engine consumes maybe 15 g/s of air total. The leak represents a big fraction of that total, so fuel trim has to add fuel aggressively to compensate. At cruise the engine consumes 100+ g/s of air; the same leak is now proportionally tiny and trim looks normal.
This is why P2187 specifically (lean at idle) is so reliably a vacuum leak diagnosis — far more so than the broader P0171 which could also be fuel-side problems.
P2187 vs P0171
- P0171 — general system too lean Bank 1. Sets when LTFT runs high across operating conditions. Could be vacuum leak, fuel pressure, MAF, or sensor.
- P2187 — specifically lean at idle. Sets when LTFT runs high at idle but not elsewhere. Strongly points at vacuum leak.
If both codes set together, the vacuum leak is large enough to affect cruise trim too. If only P2187 sets, the leak is small.
Common P2187-prone vehicles
- Ford 4.6 / 5.4 modular V8 — cracked plastic intake manifold
- Chrysler 3.6 Pentastar — intake gasket, PCV system
- GM 3.6 LFX / LLT V6 — PCV diaphragm in valve cover failure
- Honda K-series — IACV gasket, vacuum tee at brake booster
- Toyota 2GR-FE — throttle body gasket
- Most vehicles 10+ years old — hardened brake-booster hose