P2440 code meaning
AIR System Switching Valve Stuck Open (Bank 1)
Powertrain system Generic code P24xx codes Check engine light
What P2440 means
P2440 means the bank 1 secondary air shut-off (switching) valve stays open when it should be closed. GM tests it in phase 2 of its air check: the pump runs while the valve is commanded shut, so pressure in the duct should build; if it stays more than 3 kPa below the model (2005–2006 3.8L V6) or under the 2018 table limit, the code sets as Type B. Volkswagen compares measured with modelled pressure while the valve is closed (2014 Beetle below 71.1 %, Golf 2.5L below 64.8 %). Toyota and Lexus see it on 2UZ-FE, 1UR-FE and 1GR-FE trucks, often after pump debris jams the valve (T-SB-0230-12, L-SB-0028-14, T-SB-0033-17); Subaru's 2011–2015 STI guidance says to check both banks. An open valve lets hot exhaust reach the pump.
P2440 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P2440
- Check engine lamp after a cold start
- Pump noisy or failing later due to exhaust backflow
- Often stored together with P2442 or P2445
Common causes of P2440
- Most likelyValve held open by debris from a damaged pump filter
- PossibleValve seat carboned up or corroded by condensate
- PossibleElectric or vacuum actuator does not close the valve
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Secondary air switching valveSecondary air pump
What each part of P2440 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 40 | The exact fault in that area. |
What to do next
- Note P2440 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2440
What does P2440 mean?
P2440 means "AIR System Switching Valve Stuck Open (Bank 1)". P2440 means the bank 1 secondary air shut-off (switching) valve stays open when it should be closed. It is a generic code, so it means the same on every make.
Is it safe to drive with P2440?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2440 fail an emissions test?
Yes, it can. P2440 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2440 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2440 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.