P2443
Secondary Air Injection System Switching Valve Stuck Closed Bank 2
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The P2443 code means the secondary air injection system switching valve for Bank 2 is stuck closed. This is the Bank 2 counterpart to P2441. The valve cannot open during cold starts to allow fresh air into the exhaust manifold on the Bank 2 side, which means the catalytic converter for that bank is not getting the extra air it needs to heat up quickly.
The primary symptom is a longer warm-up period and rougher cold-start operation. The emissions impact is significant — without secondary air injection, cold-start hydrocarbon emissions can be several times higher than normal. Over time, the catalytic converter on Bank 2 may begin to degrade faster because it is working harder without the assistance of the AIR system.
As with other secondary air injection codes, carbon buildup is the usual suspect. The Bank 2 valve is often more difficult to reach than Bank 1 on V-configuration engines, which increases labor costs. If both banks are affected (P2441 and P2443 together), it is strongly recommended to repair both at the same time. Some owners of affected Toyota and Lexus vehicles opt for aftermarket bypass solutions, but be aware that these may not be legal in states with strict emissions testing requirements.
Severity
Symptoms
- •Check Engine Light is on
- •Extended cold start warm-up time
- •Rough idle when engine is cold
- •Higher than normal cold-start emissions
- •Failed emissions inspection
- •May trigger catalytic converter efficiency codes over time
Likely Causes
Carbon buildup or corrosion has seized the Bank 2 switching valve in the closed position.
The solenoid that opens the Bank 2 valve is not activating, leaving the valve in its default closed state.
Years of exhaust soot has packed into the valve, effectively cementing it shut.
A broken wire or disconnected connector prevents the PCM from energizing the solenoid to open the valve.
Insufficient vacuum or a cracked vacuum line prevents the valve from actuating on vacuum-operated systems.
Estimated Cost
Professional Repair
Includes parts + labor
Common Fixes
- Replace secondary air injection switching valve Bank 2
- Replace air switching valve solenoid
- Clean carbon buildup from valve and passages
- Repair open circuit in wiring
- Repair or replace vacuum lines
Shop Parts
Videos
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