Make sure you re-install it the same way when re-connecting the new vacuum lines. Also note the orientation of the non-return valve (#6), each side is color coded black & white. Upon removing the vacuum lines, we noticed the bend in line #7 had mostly closed its self off, likely the whole cause of my problem. It's oriented the opposite way they illustrated it in the photo above, the clip will be pointing to the passenger side, opposite the plug.
#Bmw e46 325xi electric solenoid valve in vacuum line drivers#
You have to push the clip towards the front of the car and then slide the switch towards the drivers side (LHD car). Once they were out of the way we were able to remove the switch. I had a friend with smaller hands help out, we took turns holding a mirror and flash light to see what we were doing. To access remove the cabin air filter housing (T25? torx), and the cover below it on the firewall (Two T25? torx also), and the plastic partition on the drivers side around the Master cylinder and DME (screw rivets). I bought a replacement switch and went to changing out the lines. I traced it back to the vacuum switch under the intake manifold. No suction against my finger, it was dead. I checked the vacuum line going to the valve which was not getting any vacuum. This wasn't good as I don't want to burn out my pump blowing air against a closed valve. I could not feel exhaust gas coming from it during a cold start. I checked the valve and noticed that it was not opening. I replaced the relay again thinking that was the culprit but that didn't work. After some troubleshooting I found the pump was working properly. Same 2 codes, Insufficient flow on banks 1 and 2. This turned out to be a bad relay, $8 later and a new relay problem solved. Two years ago I was throwing insufficient flow codes. Maybe this will help someone out to troubleshoot if they are having a similar issue. Thought I'd post a solution here to my latest Secondary Air system problems.