Toyota Tacoma P0411: Secondary Air Injection System → Incorrect Flow Detected

P0411 This is the OBDII General Trouble Code. It has the exact same meaning for both the Toyota Tacoma It would with any other truck or car.  This code signifies that an ECM detects incorrect air flow in secondary air injection systems. 

P0411: Secondary Air Injection System → Incorrect Flow Detected

To reduce exhaust emissions, the secondary air injection system injects oxygen into the exhaust.  P0411 will most often be due to a problem with the pump or one-way check valve. However, there are many other possible reasons why P0411 is thrown.

P0411 Symptoms:  Toyota Tacoma

Some symptoms of P0411 may affect your Tacoma's driving ability.  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

Tacoma P0411 Diagnosis

Typically there are three components to an AIR system.  These are the pump and hoses.  This is all electronic controlled so it's a good place to check the fuse.

An excellent scan tool can be used to control the AIR pump.  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 Valve Check

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.  These are Very affordable.  They will not accept instruction from the ECU if they do.

A Leakage in the Exhaust

ECM can be misled by an exhaust leak to believe that your AIR system may not be working properly.  Check for exhaust system damage.  If there’s a leak, you should be able to hear it.  

Conclusion 

The Toyota Tacoma may not experience a breakdown, however it could affect its 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.  You are welcome!