Subject: Before you buy any parts I would check it out. Author: Magnum : member since January, 2004 : 3968 posts Posted on: 2005-12-09 10:27:43

First check the hose coming off the front side of the airbox:


Second, check the hose that leads to the thrmostat:


If more investigation is needed it's really pretty easy to get at, take off the front bumper cover all you need is a T-50 Torx bit and a 8mm wrench or socket. Remove the 2 T-50 bolts on each side of the license plate mounting point and then remove the 2 8mm bolts at each wheel well and pull off the bumper cover. If you have PDC be careful with the wires.

The secondary air pump is on the passenger side, "X" marks the spot in the pic below. There are 2 hoses coming off it, 1 that goes to the airbox and another that goes to the thermostat. Check out for good connections and maybe start the car to see if you can tell if the pump is running.


You may also check all the connections to make sure they are clean. Here's a .pdf from the TIS that talks about a possibleSecondary Air System Failure.pdf in various models.

Good luck and I hope you can trace the problem!

• Secondary Air Injector Valve Circuit Short to Ground - what would cause this? (nt) - wcoleman 2005-12-09 10:09:34 (155 views)
  • Before you buy any parts I would check it out. (pic) (url) - Magnum 2005-12-09 10:27:43 (876 views)
    • Magnum, what's the air pump function? Emission related or - bmw635 2005-12-09 12:44:51 (190 views)
      • Air pump purpose and part numbers.... - wcoleman 2005-12-09 13:48:07 (250 views)
        • I should clarify - the mechanic at my dealer accidentally broke the - wcoleman 2005-12-09 13:59:42 (193 views)
          • Do you think the engine heat dried all these part? (nt) - bmw635 2005-12-09 14:06:04 (141 views)
            • That would be my guess...it was brittle. (nt) - wcoleman 2005-12-09 15:42:29 (126 views)
        • Woow, that's steep for secondary function purpose parts. Tks. (nt) - bmw635 2005-12-09 13:53:42 (127 views)
    • Good info. Do you happen to have the part numbers - DavidC 2005-12-09 12:15:53 (124 views)
      • Here's a digram and part numbers for the 2, a 740 & 750. (url) - Magnum 2005-12-09 17:30:12 (215 views)
    • Wow Magnum, that is a fantastic bit of help!!!! Thank you!! I love this board. (nt) - wcoleman 2005-12-09 11:11:00 (100 views)
  • I found this link to the e38 site that I believe solves my search... (url) - wcoleman 2005-12-09 10:17:14 (248 views)