2000 A6 2.7T. It's cold in Michigan now and I'm noticing that the Secondary Air Injection is not coming on when the car sits for a couple of hours in the mid twenties or colder temps. Is there a low temperature operating limit for the system? Only codes are for a converter efficiency and O2 sensor. No codes for the SAI system. Thanks for the help.

 

You have about the same temps as we do up here and my SAI has been trying to run since November. So I would think yours should be running also. Mine throws codes so thats how I know its not working lol. When I clear them, they generally come back on when the car sits more than a couple hours. So if yours is bunk, im not sure why it wouldnt throw a code.

 

I had the car in the shop recently and asked the mechanic about it. He said that I should give it more time and see what happens. It doesn't seem to be doing anything to the cats or O2 sensors. Plus, with yours being a non-turbo car, there may be differences in the systems. Thanks for the info, though.