P2440Generic code

P2440 Code: Secondary Air Injection System Switching Valve Stuck Open (Bank 1)

The P2440 code means the secondary air valve on bank 1 has stuck open, which can let exhaust gas flow back toward the pump and damage it. The car drives normally. You may not pass an emissions inspection until it is fixed.

Severity
Low
Can I keep driving?
Yes, no immediate risk
Estimated cost
$80 to $800
Difficulty
Medium
System
Emissions Control
Applies to
All OBD2 vehicles

Common in: Toyota

Updated Reviewed by Renzo Chacca

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What the P2440 code means

The secondary air system injects fresh air into the exhaust during the first minutes after a cold start. That burns off leftover hydrocarbons and warms the catalytic converter sooner. It is made up of an electric pump, a relay, a switching valve and a check valve next to the exhaust manifold.

With the valve open at the wrong time, the computer sees the oxygen sensors reading lean while the pump is off, or it detects pressure in the air line. That is the P2440 code.

The system works only for a minute or two after a cold start, so tests should be done with the engine cold.

P2440 code symptoms

  • Check engine light on.
  • The pump noise after a cold start is either present or missing.
  • Usually no driving symptoms.
  • May keep you from passing an emissions inspection.

Likely causes of the P2440 code

  1. Check valve or switching valve seized by carbon or corrosion.
  2. Vacuum solenoid that controls it stuck on.
  3. Poorly connected vacuum hoses. Look for cracks and loose clamps, especially in the hot areas.

How to diagnose the P2440 code step by step

  1. Start the engine cold and listen. The pump should run for a few seconds or minutes.
  2. Command the pump and the valve with the scan tool.
  3. Check the hoses between the pump and the manifold.
  4. Check the check valve. It should let air through only toward the exhaust.
  5. Watch the oxygen sensors with secondary air active. They should show a lean mixture.

How to fix the P2440 code

  • Replace the faulty valve or pump.
  • Clean or replace clogged passages.
  • Replace the relay if it does not switch the pump on.
  • Clear the codes and verify with a cold start.

Technical reference data

  • Secondary air pump: 12 V and a draw of 10 to 30 A.
  • Typically runs for 30 to 120 seconds after a cold start.
  • Approximate values only: check the manufacturer data for your vehicle.

Brand-specific notes

Check the check valves early. When exhaust or condensation gets back into the pump, it can ruin the pump, and the P2440 code is often the first warning of it. Check valves are damaged when condensation gets into the pump.

P2440 on Volkswagen, Audi, BMW, Mercedes-Benz and Porsche

Common on these European makes.

P2440 on Toyota Tundra and Sequoia

Seen on these Toyota models.

P2440 on Chevrolet

Seen on Chevrolet vehicles as well.

Frequently asked questions about P2440

Can I drive with a P2440 code?
Yes. The P2440 code does not affect how the car drives, though you may fail an emissions inspection.
What does secondary air injection do?
It helps warm up the catalytic converter and cut emissions right after a cold start.
Why does the air pump fail?
Because water or condensation gets in from the exhaust when the check valve fails.
What does the P2440 code mean?
It means the secondary air switching valve on bank 1 is stuck open, so air or exhaust can flow when it should not.
How much does it cost to fix P2440?
Roughly $80 to $800. A valve or hose is at the low end, and a new air pump costs the most.

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Questions about the P2440 code

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