2004 545i, so I turned my car early this morning to take my girl home before work and boom it was on.
So when i got out of work i passed by my buddies shop so he can read the code, increased emissions on the
idrive "secondary air system" on his tool. What could be the problem ?? thank youuuu

 

possibly the crankcase vacuum diaphram. someone will probably chime in with a more exact description.

 

Check your gas cap ... though there is a specific alert for that it could also trigger the SES light. The oil filler cap also do the same. Ensure both are tightened / closed correctly.

 

Just had this fixed. Secondary air is a pump that warms your engine faster so you create less emissions. The plastic hosing becomes britle and breaks. It is not covered by CPO. To replace it you have to take off the intake manifold. I had it done at an indy for $950.

 

Was there a specific code from the reader?

I've had the increased emissions problem for a while. I've found out I need to change the
activated charcoal filter (item 1 in the picture), for this to go away. If I remember correctly the code for this was 1439.

 

ofcourse there was a specific code, that's how he knew it was secondary air.

 

Actually, the purpose of the secondary air pump is merely to test the health of the Oxygen (O2) sensors. The air pump injects air into the exhaust system ahead of the primary O2 sensors during cold starts only. The DME looks for the O2 sensor(s) to report a lean condition. If the O2 sensor(s) do not behave as expected, then a fault code is stored. Can mean either the air is not being injected, or the O2 sensor(s) is faulty.

 

I guess my Service Advisor and Indy were both wrong as the independently explained what it does....

I agree it heats the 02 sensors.

 

Yep, they are wrong. The air pump in no way aids in accellerating the heating of the O2 sensors, that is what the heating element in the O2 sensor is for.

 

really cause this is all over the place online, most notabley from a BMW tech.

The SAP runs upon engine startup for 90 seconds. It injects air (oxygen) into the exhaust gases to allow any unburnt hydrocarbons to have sufficient oxygen to burn off, and to help the O2 sensors to heat faster. This is due to ( the emissions system (O2 sensors) to be running in 'Open Loop' mode and the DME using a default fuel mapping. The system will go into 'CLosed Loop' mode when the O2 sensor heaters reach approximately 600'.