Decoding Code P0411 The Ultimate Troubleshooting Guide

It came up as P0411 Secondary Air Injection System Incorrect Flow Detected. Any ideas what this could be? The car seems to be fine with no funny noises. I know its a 2 stage test, with part of it being valve open and pump on and then part pump on and valve closed and I know the pressure increases the vehicle is ... I have 2010 Chevy impala LT 3.5 with stupid P0411 air injection incorrect flow code. I have changed the air injection pump itself the metal valve pipe that ... Most of the time with this code it is the check valve on the head that freezes up and won't open. Thus, when the pump runs, no flow is detected ... It used to be this code was set if if I had two consecutive cold starts in 20 degree Fahrenheit or below weather. No big deal. OBD-II code P0411 means you've either put the one-way valve backwards, have a leak or loose vacuum hose or routed them incorrectly. I have a code that comes up lately P0411 Mod$10, secondary air injection, incorrect flow. I have looke on youtube and have not found anything showing a vw fix ... I bought a new smog pump and a new check valve. i swapped out both parts valve and pump. Only code i get now is P0411. when starting the car now the pump is ... P0411 Code: Secondary Air Injection Incorrect (OBD-II). Jump to Latest. That code is for the secondary air injection for incorrect flow. Typically what will throw the code is when someone installs a flex fuel kit they put the ...