What it means
Compressor outlet switching valve mechanically stuck open — sequential boost cannot transition stages cleanly.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The compressor outlet switching valve controls airflow between stages in a sequential turbocharging system. The engine control module compares the valve's expected operation with its response and sets P22CD when it detects that the valve remains open when it should close. This can disrupt the handoff between boost stages.
Common causes
Most likely first.
- Valve stuck open
- Carbon or debris buildup preventing free movement
- Component wear with age - mechanical play
Symptoms
- Check engine light on
- Reduced engine power or poor acceleration
- Possible abnormal boost response
How to diagnose it
- Record freeze-frame data and check live boost and valve data, if available, to see when the open position was detected.
- Inspect the compressor outlet valve and nearby intake plumbing for damage, loose connections, or signs that the valve is not seated.
- Check the valve linkage or actuator for free movement and look for carbon or debris that could hold it open.
- Inspect the valve connector and wiring for corrosion, damaged insulation, or loose terminals that could affect its position feedback or control.
- If the valve moves freely and its wiring is intact, test its operation and position feedback using the manufacturer's procedure before replacing parts.
Common fixes
- Remove accessible carbon or debris that is preventing the compressor outlet valve from closing.
- Repair loose, damaged, or corroded valve connector terminals and wiring.
- Repair or replace a sticking valve actuator or linkage.
- Replace the compressor outlet switching valve if it remains mechanically open after cleaning and inspection.
Can I keep driving?
Drive gently and avoid hard acceleration or towing because the turbo stages may not switch correctly and power can drop. Stop if power loss becomes severe or the engine shows signs of overheating or abnormal turbo noise.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.