Fuzzuki - Here's what I did to kill the dreaded SAI code.
Need Professional Help Diagnosing with Durametric Data
To cut to the chase on the thread, the SAI comes down to a blower moving air through the heads directly into the exhaust manifold ahead of the cats.
If the air does not appear on cue, you get the codes.
This occurs at a cold start when the temp is below about 70F, but it also occurs while you are stopped idling after going down the road as part of a drive cycle check. Sneaky.
So, what to check?
Vacuum leak as already noted. The valves are driven by vacuum, lose that, and you get the codes
The valves may not be operating - change them - it's a booger.
Under the rear trunk liner that covers the left rear fender there's a big honking green fuse . Check that fuse. If it is blown there's likely a vacuum problem that helped it blow, the blower fan was dead headed. Mine was blown because my changeover valve was not opening due to lack of vacuum - all that is in the string above.
There are also computer wires that run the solenoid valve for the changeover valve - if they are damaged then the system will fail, but that does not seem likely.
Best of luck!
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