Yes, the pump fixed the problem. Haven't had any problems thus far.

Dan

Thank you for reply so quick!
The SES light is not on any more after I replace the secondary air valve. My air pump went very noise in the morning, is your new air pump very quite? (I just want verify before I replace new one).
Did you have any problem with you engine beside the SES light on before you change the new air pump?
Again, Thank you for your advice

Mine had the exact same problem. Noisy pump and the SES light would come on after a few days from resetting the light. The new pump is quieter as compared to the old one.

Dan

Oh great....Check engine light came on this afternoon....P0491 and P0492 error codes again. I bet the smog pump or valve tanked. Perfect timing too....just a hair over two years, so no more BMW parts warranty =( I hope the light will not come on again.

Its an emissions device that pumps air into the engine during cold starts to assist in getting the cats up to temp. You're fine driving it till you get it fixed, but don't drag your feet on replacing it either cause cats aren't cheap.

BUMP, I've had the error for mine for over a year now and haven't bother replacing it. The pump does not make any noise (from what I can hear) or it's just quiet.. If the secondary air pump were to be the issue, i assume it would causes loud noises as people mentioned? Can I safely assume that since it doesn't produce any noise or minimal noise that it might be just a crack vacuum line?

I had same problem, the pump was tested and was fine, no vacuum leak, but apparently the metal tubing that carries the air to the exhaust can get clogged up with carbon or whatever. My mechanic ran water through the lines, got out all the debris, and now the codes are gone and no problems for 3 months.