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Code P2440

Symptoms

• Check Engine Light is on

• Increased emissions

• Poor engine performance

Common Causes

• Faulty air switching valve

• Damaged or leaking vacuum hoses

• Faulty air pump

Glossary

AIR System: Secondary Air Injection System, used to reduce emissions.

Bank 1: The side of the engine with cylinder 1, typically the driver's side in a V-engine.

Related Codes

• P2441

• P2442

Official description

AIR System Switching Valve Stuck Open Bank 1

Laymans terms

This code means that a part of your car's system that helps reduce pollution is not closing properly, kind of like a door that's stuck open when it should be closed.

Explanation

The P2440 code indicates that the secondary air injection system's switching valve for bank 1 is stuck open.

Technical description

The secondary air injection system is designed to reduce emissions by injecting fresh air into the exhaust system during cold starts. The system uses switching valves to control the flow of air. When the valve is stuck open, it can cause improper air flow and increased emissions.

Diagnosis steps

• Use an OBD-II scanner to confirm the code.

• Inspect the air switching valve and related hoses for damage.

• Test the functionality of the air pump.

Repair procedures

• Replace the faulty air switching valve.

• Repair or replace damaged vacuum hoses.

• Replace the air pump if necessary.

Tools required

• OBD-II scanner

• Vacuum gauge

• Wrench set

Estimated repair cost

$150 - $500

Difficulty level

Moderate

Commonly affected vehicles

• Toyota Tacoma

• Lexus GX470

• Toyota Tundra

Preventive measures

• Regularly inspect and maintain the air injection system.

• Replace air filters as recommended.

• Check for vacuum leaks periodically.

Error code type

Emission Control Issue

User experience recommendations

• Have your vehicle inspected by a professional mechanic.

• Avoid driving with the Check Engine Light on for extended periods.

• Regular maintenance can prevent this issue.

Warranty information

Check with your vehicle manufacturer, as emissions-related components may have an extended warranty.

Historical data

The P2440 code has been more common in vehicles with secondary air injection systems, especially in certain Toyota and Lexus models.

Urgency level

Moderate – While the vehicle may still be drivable, it's important to address this issue to prevent increased emissions and potential engine damage.

Legal and safety notice

Driving with a malfunctioning emissions system may violate local emissions laws and can contribute to environmental pollution.

Testing conditions

• Engine at operating temperature

• Cold start conditions

Component location

The air switching valve is typically located near the engine, connected to the exhaust manifold.

FAQs

Q: Can I drive with a P2440 code?
A: While you can drive with this code, it's best to have it fixed to avoid increased emissions and potential engine damage.

Q: How do I reset the Check Engine Light after fixing the issue?
A: You can reset the light using an OBD-II scanner, or it may turn off automatically after several drive cycles if the issue is resolved.

Last updated: Mar 2, 2026 • Source: internal database
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