Powertrain, generic (extended)

P2440 AIR System Switching Valve Stuck Open (Bank 1)

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

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.

Likely causes

Valve held open by debris from a damaged pump filter
Valve seat carboned up or corroded by condensate
Electric or vacuum actuator does not close the valve

Symptoms

  • Check engine lamp after a cold start
  • Pump noisy or failing later due to exhaust backflow
  • Often stored together with P2442 or P2445

Repair estimate

DifficultyMediumDIY possible
Parts and labour€120–900
Time0.5–3 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

secondary air switching valvesecondary air pump

Related codes

P2441P2442P2444P0411P0412

References: gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov, static.nhtsa.gov.