Powertrain
generic / SAE
P0411
Secondary Air Injection System Incorrect Flow
When the ECU commands secondary air injection, the actual flow measured by the front oxygen sensor (or a dedicated mass flow meter) does not match the expected value. Usually a partially blocked passage or a leaking combi valve.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / 11
Possible causes
- Air passages in cylinder head clogged with carbon high
- Air pump weak medium
Inspection / repair
- Difficulty: medium
- DIY: possible
- Estimated cost: 150–1000 €
- Estimated time: 1–6 h
- Component: secondary air pump
- Component: secondary air valve
- Component: secondary air passages
- MIL / check engine light
- emissions-relevant
- drive cycle required
Sources
References
sae:J2012