p0411
Moderate
Audi · Sedans
Secondary Air Injection System Incorrect Flow Detected
Quick Answer
Error code P0411 on your Audi Sedans means: Secondary Air Injection System Incorrect Flow Detected. This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Activate the secondary air pump using a diagnostic scan tool and listen for pump operation
2
Check the secondary air pump relay and fuse for proper function
3
Inspect the combi valve for carbon buildup or mechanical failure
4
Test the secondary air hoses for blockages or leaks
5
Verify airflow is reaching the exhaust manifold by checking the combi valve passages
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Secondary air injection pump
Combi valve (secondary air valve)
Secondary air hoses
Secondary air pump relay
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