P2443 code meaning
AIR System Switching Valve Stuck Closed (Bank 2)
Powertrain system Generic code P24xx codes Check engine light
What P2443 means
P2443 signals that the bank 2 secondary air valve stays shut although the engine computer commands it open, so the second bank gets no added air during warm-up. Subaru lists the code for the 2011–2015 WRX STI and recommends always following the diagnosis for the opposite bank too, since valve or hose faults on one side can show up on the other. Toyota's 2UZ-FE bulletin covers only the bank 1 equivalent. Under CARB rules, each bank's air supply must be judged on its own wherever a blocked bank would raise emissions measurably. Common causes are a seized valve, a leaking vacuum supply or control solenoid, and kinked hoses. Expect slightly higher cold-start emissions and a failed readiness check; driving is normal. P2441 is the bank 1 code.
P2443 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 P2443
- Check engine lamp after a cold start
- Secondary air readiness not set
Common causes of P2443
- Most likelyBank 2 valve seized in the closed position
- PossibleLeaking vacuum line or faulty control solenoid
- Less likelyKinked air hose on the bank 2 side
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 vacuum lines
What each part of P2443 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). |
| 43 | The exact fault in that area. |
What to do next
- Note P2443 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 P2443
What does P2443 mean?
P2443 means "AIR System Switching Valve Stuck Closed (Bank 2)". P2443 signals that the bank 2 secondary air valve stays shut although the engine computer commands it open, so the second bank gets no added air during warm-up. It is a generic code, so it means the same on every make.
Is it safe to drive with P2443?
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 P2443 fail an emissions test?
Yes, it can. P2443 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 P2443 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 P2443 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.