P2440🌫 Emissions (secondary air injection)Drive with caution, fix soon

P2440: Secondary Air Switching Valve Stuck Open Bank 1 (Meaning, Causes, Fixes)

Reviewed 2026-10-24 · Based on 4 cited source(s)

What P2440 means

The secondary air injection system pumps outside fresh air into the exhaust during a cold start. RepairPal explains that this extra air helps burn off the very rich exhaust the engine makes while warming up. The system usually has an electric air pump, tubes to route the air, and a solenoid and check valves to control the airflow. Toyota calls the valve an air switching valve, and V8 trucks have one for each bank. P2440 is set when the engine computer finds a fault with that valve on bank 1, and the code's official title says the valve is stuck open. P2442 is the same fault on bank 2, while P2441 and P2443 are the stuck closed versions. RepairPal only explains P2440 as a general secondary air injection fault, so check your vehicle's service information for exactly how your engine tests the valve.

Severity: can I keep driving?

Drive with caution, fix soon

Usually not an emergency, but get it diagnosed within a reasonable time. RepairPal rates P2440 as Moderate. The check engine light will likely fail an emissions inspection, and Toyota says some 2014 to 2016 Tundras with this code can go into limp mode with throttle limited to about 25 mph, so don't ignore it if the truck feels down on power.

Common symptoms

Likely causes

Roughly most to least common, based on the sources below. Your vehicle may differ.

  1. Water or moisture inside the air injection pumps and air switching valves, which Toyota acknowledged on certain 2011 Tundra and Sequoia trucks (Toyota Warranty Policy Bulletin POL17-02)
  2. Air injection pump filter damage on 2012 Tacoma with the 4.0L V6 (Toyota T-SB-0333-17)
  3. Sub-freezing temperatures on 2014 to 2016 Tundra 5.7L, fixed with an engine computer update (Toyota T-SB-0079-16)
  4. A failed secondary air pump control valve (RepairPal)
  5. A failed secondary air pump (RepairPal)
  6. A clogged or disconnected vacuum hose (RepairPal)
  7. A wiring problem (RepairPal)
  8. A failed engine computer, which is rare (RepairPal)

Diagnostic steps you can do

⚠ Before you start

Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.

  1. Read all stored codes and freeze frame data and write them down. P2440 often shows up with P2442, P2445 or P0418 on Toyotas, which points at the shared pump and valves.
  2. Look up technical service bulletins and warranty programs for your VIN. Toyota has several for this code, and some extended coverage well beyond the normal warranty.
  3. Note the weather when it set. On 2014 to 2016 Tundras, Toyota says sub-freezing temperatures can trigger it and the fix is a software update at the dealer.
  4. Inspect the air pump, the switching valves, and the hoses and wiring between them for cracks, loose connections, disconnected hoses, and corrosion.
  5. Check the air pump inlet and filter area for water, dirt or damage. Toyota's bulletins have the pump and the air switching valves replaced together when water or filter damage is found, and T-SB-0333-17 says all listed parts must be replaced to avoid a comeback.
  6. Clear the code and see if it returns after a cold start, since the system only runs while the engine is warming up.

Typical fixes

Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.

🛠 When to call a pro

  • You have a Toyota Tundra, Sequoia or Tacoma, since a dealer can check bulletins and warranty coverage for your VIN first
  • The truck goes into limp mode or loses power
  • You don't have a scan tool that can command the air pump and valves for testing
  • You need the light off for an inspection deadline

Where to buy

Plain search links. Always match parts to your exact year, make, model and engine.

OBD2 scanners on Amazon Parts at Advance Auto Parts catalog at RockAuto

FAQs

Is P2440 serious?

Usually not an emergency. RepairPal rates it Moderate. But Toyota says some 2014 to 2016 Tundras can go into limp mode at about 25 mph with this code, so get it checked soon, especially if the truck feels down on power.

Why is P2440 so common on the Toyota Tundra?

Toyota has issued several bulletins about it. On certain 2011 Tundras and Sequoias, Toyota extended coverage for moisture or water getting into the air pumps and air switching valves. On 2014 to 2016 Tundras with the 5.7L, cold weather can set the code, and the fix is an engine computer update.

Will Toyota cover P2440 under warranty?

It depends on your VIN. Toyota's warranty enhancement program ZG6 covers moisture in the air pumps and switching valves on certain 2011 Tundra and Sequoia trucks for 10 years or 150,000 miles from first use, and the 2014 to 2016 Tundra software update is listed under the federal emission warranty of 8 years or 80,000 miles. Ask a Toyota dealer to check your VIN.

Do the sources agree on P2440?

Mostly, but they focus on different things. RepairPal describes it as a general secondary air injection fault and lists vacuum hoses, the pump, the control valve, wiring and the engine computer. Toyota's bulletins are model-specific and point to water in the pump and valves, a damaged pump filter, or cold-weather triggering fixed by software. OBD-Codes.com has no full article for P2440, only forum threads.

How much does it cost to fix P2440?

Neither source gives a repair cost. It ranges from a free software update or a hose fix to replacing the pump and both valves, so check for warranty coverage first and get a written estimate after diagnosis.

Sources

  1. RepairPal: P2440 Secondary Air Injection System Switching Valve Stuck Open (rated Moderate)
  2. Toyota T-SB-0079-16: MIL ON DTC P2440/P2442, 2014-2016 Tundra 1UR-FE (via NHTSA)
  3. Toyota T-SB-0333-17 Rev1: Secondary Air Injection System MIL ON DTC P2440, P2442, P2445, 2012 Tacoma 1GR-FE (via NHTSA)
  4. Toyota Warranty Policy Bulletin POL17-02: Warranty Enhancement Program ZG6, air injection pumps and air switching valves, 2011 Tundra and Sequoia (via OEMDTC)

Last reviewed 2026-10-24. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.