P2440 on Toyota
Secondary Air Injection System Switching Valve Stuck Open (Bank 1)
P2440 on Toyota vehicles indicates secondary air injection system switching valve stuck open (bank 1). Au7o has documented this code across 4 Toyota models — most commonly on 4Runner, Land Cruiser, Sequoia. P2440 indicates the secondary air injection (SAI) system's switching/diverter valve on engine bank 1 is stuck open. The secondary air system briefly pumps fresh air into the exhaust at cold start so the catalytic converter heats up and lights off faster, cutting cold-start emissions. The computer commands this valve closed once warm-up is done; if it senses the valve hasn't closed (air is still flowing when it shouldn't be), it sets this code. A stuck-open valve can let exhaust pressure or moisture back into the air pump and skews the oxygen sensor readings during warm-up. Typical repair costs on Toyota range from $100 to $3,000, depending on the specific model and root cause.
Common Causes of P2440
- •Air switching/diverter valve stuck open or seized
- •Carbon, rust, or debris fouling the valve
- •Faulty valve vacuum control solenoid or leaking vacuum line
- •Corroded or moisture-damaged secondary air pump
- •Wiring or connector faults at the valve solenoid
- •Clogged or failed combination/check valve
- •Vacuum leak preventing the valve from closing
P2440 on Toyota by Model
Toyota 4Runner(1 issue)
- Secondary Air Injection Pump/Valve Failure Triggering Limp Mode on 4.7L V82005-2009
The 4.7L 2UZ-FE V8 used in later 4th-generation 4Runners is known for secondary air injection system failures involving the air pump and switching valves. When the system sticks or fails electrically, the truck may illuminate the check engine light and enter reduced-power or limp mode. This problem is widely documented across Toyota V8 trucks and SUVs of the era and can be very expensive when repaired with OEM components.
Toyota Land Cruiser(2 issues)
- Secondary Air Injection Pump Failure (200 Series)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.
- Secondary Air Injection System Failure (100-Series, 4.7L V8)1998-2007
The secondary air injection (AI) system on the 100-series Land Cruiser (1998-2007) with the 2UZ-FE 4.7L V8 is a notorious failure point, identical to the issue on the Sequoia and Tundra of the same era. The electric AI pump, air switching valves (ASV), and exhaust manifold check valves all fail. The aluminum check valves in the exhaust manifolds corrode and seize, the ASV sticks from carbon buildup, and the pump motor eventually burns out. This system is responsible for the most common check engine light on 100-series Land Cruisers.
Toyota Sequoia(2 issues)
- Secondary Air Injection System Failure (2UZ-FE)2001-2009
The 4.7L 2UZ-FE's secondary air injection system fails due to corroded air switching valves (ASVs) and seized air pumps. Moisture enters the system and corrodes internal components. Causes check engine light with P2440/P2442 codes.
- Secondary Air Injection Pump Failure (3UR-FE/i-FORCE)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.
Toyota Tacoma(1 issue)
- Secondary Air Injection Pump and Switching Valve Failure on 4.0L V62005-2011
Tacomas with the 1GR-FE 4.0L V6 are known for failures of the secondary air injection system, including the air pump and switching valves. Moisture intrusion and valve sticking can trigger check-engine lights and force the truck into reduced-power or limp mode. Owners frequently report sudden loss of acceleration along with expensive dealer repair estimates because the intake manifold often must be removed to access components.
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View P2440 across all makes →Frequently Asked Questions
What does P2440 mean on Toyota?▼
P2440 stands for "Secondary Air Injection System Switching Valve Stuck Open (Bank 1)." P2440 indicates the secondary air injection (SAI) system's switching/diverter valve on engine bank 1 is stuck open. The secondary air system briefly pumps fresh air into the exhaust at cold start so the catalytic converter heats up and lights off faster, cutting cold-start emissions. The computer commands this valve closed once warm-up is done; if it senses the valve hasn't closed (air is still flowing when it shouldn't be), it sets this code. A stuck-open valve can let exhaust pressure or moisture back into the air pump and skews the oxygen sensor readings during warm-up. On Toyota specifically, this code is documented across 4 models.
What causes P2440 on Toyota vehicles?▼
Common causes on Toyota: Air switching/diverter valve stuck open or seized, Carbon, rust, or debris fouling the valve, Faulty valve vacuum control solenoid or leaking vacuum line, Corroded or moisture-damaged secondary air pump, Wiring or connector faults at the valve solenoid. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2440 on a Toyota?▼
Repair costs on Toyota range from $100 to $3,000, depending on the specific model and root cause.
Which Toyota models have P2440 documented?▼
Au7o has documented P2440 on 4 Toyota models: 4Runner, Land Cruiser, Sequoia, Tacoma.