P2442 on Lexus
Secondary Air Injection System Switching Valve Stuck Open (Bank 2)
P2442 on Lexus vehicles indicates secondary air injection system switching valve stuck open (bank 2). Au7o has documented this code across 1 Lexus model — most commonly on GX. This is an emissions-system code, and it's the opposite condition of P2443. The secondary air injection system briefly pumps fresh air into the exhaust after a cold start so the catalytic converter warms up and cleans pollutants more quickly. P2442 means the switching (changeover) valve on Bank 2 — the cylinder bank that does not contain cylinder 1 — appears stuck in the open position, allowing air to flow when it shouldn't. The computer detects this through pressure/flow sensing or by seeing an oxygen-sensor reading that's leaner than expected when the air pump should be off. It's an emissions and inspection issue, not a drivability emergency. Typical repair costs on Lexus range from $800 to $2,000, depending on the specific model and root cause.
Common Causes of P2442
- •Switching/changeover valve stuck or sticking open (Bank 2)
- •Carbon, debris or corrosion holding the valve open
- •Failed vacuum or electric solenoid controlling the valve
- •Vacuum hose leak, crack or wrong routing to the valve
- •Leaking or failed check/combination valve
- •Wiring or connector fault to the control solenoid
P2442 on Lexus by Model
Lexus GX(1 issue)
- Secondary Air Injection Pump Failure2003-2009
The secondary air injection (SAI) system pump and switching valves fail due to moisture intrusion and corrosion. The SAI pump introduces fresh air into the exhaust during cold starts to reduce emissions, but the pump motor corrodes internally and the switching valves stick. This triggers a check engine light with SAI-related codes.
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View P2442 across all makes →Frequently Asked Questions
What does P2442 mean on Lexus?▼
P2442 stands for "Secondary Air Injection System Switching Valve Stuck Open (Bank 2)." This is an emissions-system code, and it's the opposite condition of P2443. The secondary air injection system briefly pumps fresh air into the exhaust after a cold start so the catalytic converter warms up and cleans pollutants more quickly. P2442 means the switching (changeover) valve on Bank 2 — the cylinder bank that does not contain cylinder 1 — appears stuck in the open position, allowing air to flow when it shouldn't. The computer detects this through pressure/flow sensing or by seeing an oxygen-sensor reading that's leaner than expected when the air pump should be off. It's an emissions and inspection issue, not a drivability emergency. On Lexus specifically, this code is documented across 1 model.
What causes P2442 on Lexus vehicles?▼
Common causes on Lexus: Switching/changeover valve stuck or sticking open (Bank 2), Carbon, debris or corrosion holding the valve open, Failed vacuum or electric solenoid controlling the valve, Vacuum hose leak, crack or wrong routing to the valve, Leaking or failed check/combination valve. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2442 on a Lexus?▼
Repair costs on Lexus range from $800 to $2,000, depending on the specific model and root cause.
Which Lexus models have P2442 documented?▼
Au7o has documented P2442 on 1 Lexus model: GX.