P2443: How to Diagnose & Fix — Secondary Air Injection System Switching Valve Stuck Closed (Bank 2)
5 vehicles · 2 makes · $300-$4,000 repair
How to diagnose and fix P2443: most-reported vehicles
Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.
Toyota Tundra · 2005–2013
The secondary air injection pump is prone to failure due to water intrusion. The electric motor is located in the wheel well with moisture exposure, and the rubber boot covering the motor traps water, causing the pump to short circuit. This triggers check engine lights with codes P2440, P2443, P2445, P2447, P0418, or P0419. Some vehicles may enter limp mode.
Common Symptoms
- Check engine light illumination
- Jet engine noise on cold startup
- Decreased fuel economy
- Limp mode activation
- Rough idle when cold
How to Fix
Toyota issued a service bulletin for 2007-2010 models covering replacement of the entire air injection system. Repair costs range from $2,000-$4,000 for OEM replacement. Some owners opt for aftermarket bypass kits with block-off plates.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Toyota 17610-0S010 genuine secondary-air pump assembly
replace the corresponding pump only when active testing and the applicable Toyota program identify it as failed Fitment/availability: Cataloged for selected 2007-2013 Tundra applications; exact engine, side/quantity, DTC branch, VIN and …
- Toyota 17610-0S030 genuine secondary-air pump assembly
replace the program-matched pump after active-test confirmation, with all required valves, inlets, gaskets and calibration handled separately Fitment/availability: Cataloged for selected 2012-2021 4.6L/5.7L applications; on this card use…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Owner tips & cautions
- TipDIY repairs can save significantly - dealer charges $2,000-$4,000 but DIY costs are typically 50-70% less
- TipConsider OEM parts for critical components like sensors and electrical parts - aftermarket can be unreliable
- TipGet a proper diagnosis before replacing parts - similar symptoms can have different causes
Toyota Sequoia · 2008–2019
2nd-gen Sequoias with the 5.7L 3UR-FE also suffer from secondary air injection pump failures, similar to the 1st gen but with updated part numbers. The pump seizes from internal moisture corrosion, triggering P2440-P2445 codes and check engine light.
Common Symptoms
- Check engine light with P2440-P2445 codes
- Loud buzzing or grinding on cold start
- Air pump not engaging on startup
- Failed emissions test
How to Fix
Replace secondary air injection pump (Toyota 17610-0S010 or Dorman 306-058). Replace air switching valves if corroded. Aftermarket pumps are available at lower cost. Some owners install check valves in the air line to prevent moisture backflow into the pump.
Toyota Land Cruiser · 2008–2021
The secondary air injection system on the 200 Series Land Cruiser (3UR-FE and later engines) fails due to moisture intrusion and corrosion of the air switching valves and pump motor. The system pumps air into the exhaust manifold during cold starts to reduce emissions. When it fails, it triggers check engine lights and can prevent the vehicle from passing emissions testing.
Common Symptoms
- Check engine light on cold starts
- Rough idle for first 30-60 seconds
- Whirring noise from engine bay on startup
- Failed emissions inspection
- Multiple air injection fault codes
How to Fix
Replace the air injection pump, air switching valves, and check valves. Clean or replace corroded wiring connectors. Some owners delete the system entirely with aftermarket tune, though this prevents passing emissions in tested states. Toyota TSB-0111-10 addresses the updated valve design.
What you need to fix it
Only diagnosis- and fitment-reviewed repair parts are linked here.
- Toyota 17610-0S010 genuine secondary-air pump assembly
early pump branch, replacing only the unit proven failed by command and electrical/flow testing Fitment/availability: VIN- and production-date-confirmed 2008 through early-2013/2014 Land Cruiser 3UR-FE branch; catalog requires quantity t…
- Toyota 17610-0S030 genuine secondary-air pump assembly
later pump branch after component-specific diagnosis Fitment/availability: VIN- and production-date-confirmed late-2013 through 2021 Land Cruiser 3UR-FE branch; catalog requires quantity two Fitment/availability: Live direct product page…
- Toyota 25701-38064 genuine electric air-control valve assembly
replace only after active testing proves the electric valve is stuck, leaking or electrically failed Fitment/availability: VIN-confirmed 2008-2021 Land Cruiser 3UR-FE catalog branch; exact production supersession and associated gaskets m…
As an Amazon Associate, we earn from qualifying purchases; other part links may also earn au7o a commission. Confirm fitment by VIN before buying.
Owner tips & cautions
- TipRequest the updated air switching valve design per TSB-0111-10 when replacing - the revised valves have better moisture sealing.
- WarningDeleting the air injection system will cause a permanent CEL and emissions test failure. Only viable in non-emissions states.
Subaru WRX STI · 2008–2014
Toyota Tacoma · 2005–2011
Find P2443 by make
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P2443 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P2443 mean?
P2443 stands for "Secondary Air Injection System Switching Valve Stuck Closed (Bank 2)." This code is part of your car's emissions system. The secondary air injection system pumps fresh air into the exhaust right after a cold start to help the catalytic converter heat up and burn off pollutants faster. P2443 means the switching (changeover) valve that controls this airflow on Bank 2 — the side of the engine that does NOT contain cylinder 1 on a V-style engine — appears stuck in the closed position, so the expected air isn't reaching the exhaust. The computer detected this either by monitoring air pressure/flow or by seeing the wrong oxygen-sensor response during the cold-start air pump test. It's an emissions and inspection concern rather than something that will strand you.
What are the most common causes of P2443?
The most common causes of P2443 are: Stuck or seized secondary air injection switching/changeover valve (Bank 2), Carbon, moisture or rust buildup inside the valve or air passages, Failed vacuum or electric solenoid that operates the switching valve, Disconnected, cracked or collapsed vacuum hose to the valve, Failed or weak secondary air injection pump, Wiring or connector fault to the valve/solenoid, Clogged combination valve or check valve preventing airflow. The specific cause varies by vehicle.
How much does it cost to fix P2443?
Repair costs for P2443 range from $300 to $4,000, depending on the vehicle and root cause.
Which vehicles are affected by P2443?
Au7o has documented P2443 across 5 vehicle models from 2 manufacturers: Subaru, Toyota.
Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.