If you have trouble identifying a vacuum leak you should get a copy of the RAVE and read up on the test procedures. It appears the SAI pump will run as the ECM tries to figure out what's wrong with the system.

If the normal operation of the passive SAI diagnostics cannot be completed, (SAI operation being suspended by load/speed conditions, for instance) the ECM will attempt to perform an 'Active' test of the system when conditions allow. These conditions include, but are not limited to: 'Engine fully warm' and 'Engine at idle'. The active test comprises two parts; a 'Leak Test' followed by a 'Flow Test'....

A faulty relay would not cause a code but a malfunction in the SAI system would likely register a code and initiate the self test procedures mentioned above.

Good luck, definitely curious what you find.

 

thanks. I'll plug it in and see. Nanocom time!