Re: Faulty Secondary Air Pump - three in 10 months
My daughter has a 2003 Z4 with 54000 miles and also got the P0411 Secondary Air Injection Sytem Incorrect Flow Detected code and I discovered the air pump was bad and replaced it at Thanksgiving 2008. Within two weeks that pump stopped working so I replaced that pump as well as the check valve that attaches to the head and the relay that controls the pump. She still get the code so I removed the pump and check valve and ran a bench test. There is no flow through the check valve so I guess the last pump does not have the required pressure to open the check valve. I checked it with the old and new check valves with the same result. It appears BMW has a bad batch of air pumps.