Empowering You Troubleshooting P0411 with Clarity

The code is set when the pressure switch doesn't sense the correct pressure from the pump. I'm pretty sure the pressure sensor is part of the check valve. A common issue with GM, VW and Audi vehicles are air injection flow codes like p0410, p0411, and p0412. P0411 indicates that the ECU has detected the flow from the secondary air injection system to be out-of-specification. The P0411 code is set, it means that the PCM doesn't detect an appropriate drop in the voltage from the O2 sensor, which would indicate air being injected into ... The code is letting you know that the ECM has detected incorrect flow in the secondary air injection system. It can be hard to differentiate between actual faults and mere oddities of the OBD system itself. I had a P0411 once. Pump failed. I unplugged ... 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 ... 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 ... The 373 relay in the ECM box is the SAIP relay. The circuit to the SAIP is: battery to 40A fuse, fuse to relay contact, contact to SAIP. The secondary air injector is the leaf blower on the passenger side engine. The motor goes out usually because the relay is junk and gets stuck closed.