P0411
AIR System A Incorrect Flow Detected
Powertrain · Generic (all makes)System: Emissions
Safe to drive short term. Book a repair.
Likely causes
- Failed secondary air pump
- Stuck check valve
- Blown relay or fuse
What to check first
Check the pump relay and fuse first; failed pumps and check valves are common on older Toyota, GM and BMW engines.
Typical repair cost
$200 – $900
Independent-shop parts and labor for the usual fix. Your price depends on the actual cause and the vehicle.
Next step
General information, not a diagnosis of your vehicle. Repair costs are typical shop ranges, not quotes.