Volkswagen Passat P0411: Secondary Air Injection System → Incorrect Flow Detected

P0411 It is an OBDII general trouble code that has the same meaning as the Volkswagen Passat As it would for any other vehicle.  The code tells you that your ECM detected an incorrect flow in the secondary injection system. 

P0411: Secondary Air Injection System → Incorrect Flow Detected

Secondary air injection injects air into exhaust to reduce emissions.  Most often, the reason P0411 occurs due to failure of this pump or the one-way valve. However, there are many other possible reasons why P0411 is thrown.

P0411 Symptoms:  Volkswagen Passat

The symptoms P0411 could cause some issues with your Passat, including the inability to drive.  The following symptoms are most commonly seen:

• Backfiring-  If the AIR system is not running right, the extra fuel vapor in the exhaust can combust under hard acceleration.
• Rich condition

Passat P0411 Diagnosis

Usually, the AIR system has three major components.  The pump, the hoses and the one-way check valve are all important components of an AIR system.  It is possible to inspect the fuse for all of these electronic controls.

You can use a scan tool to turn the AIR pump ON.  If it doesn’t respond, you’ll know that it’s gone bad.

Here’s a great video on diagnosing this code from Flat Rate Mechanic:

One-way Check Valve

P0411 most commonly occurs when a single-way valve fails.  If it happens, moisture can enter the pump.  The winter can cause this moisture to freeze.

Frozen water can cause the air pump to freeze and blow its fuse.  This fuse is usually located under the vehicle's hood.  That’s a great place to start looking.   A quick glance will tell you if there is an issue.

AIR Pump

This is most commonly caused by P0411.  They can be found here It is very affordable.  They will not accept instruction from the ECU if they do.

Check for Leakage

ECMs can think the AIR system has failed because of an exhaust leak.  Check for exhaust system damage.  If there’s a leak, you should be able to hear it.  

Conclusion 

The Volkswagen Passat P0411 does not cause vehicle damage, but it could affect the car's drivability.  Any time the check engine light comes on, it’s a good idea to service it as soon possible though.

Please leave comments below if you have any suggestions.  We wish you all the best!