Actually James ,I think you are saving the Planet and us specifically because you tirelessly perused this problem with inventive,inexpensive test equipment (on video too !) and listed all the tests you did.
You explained all the frustrating results.You explained how the system worked and demonstrated it using a vac pump simulation. I do not recall anyone else doing so much to completely understand the SAI system and use it as a teaching aid.
You bought parts, hunted/fixed vacuum leaks. You even discussed DME and complex wiring/connector faults. All this in one Thread. Very useful to future SAI warriors.
Despite all this effort, no resolution.
Partially the unresolved issue is a lack of a 100 % reliable Drive Cycle protocol for SAI faults. Imagine if the only problem is : You already fixed all SAI faults days ago.All that is missing is an effective Drive Cycle to complete the Readiness Tests.
Ahsai has Posted a simplified Drive Cycle that worked for him. Some of the previous Drive Cycles were impossible to do on public roads. Note the link below- some of the gotchas - like fuel level !
https://rennlist.com/forums/996-forum/967184-smog-geeks-help-needed-obdii-monitors-not-ready.html#post13818633
Doesn't Bentley have the 2003 Wiring Diagrams ?
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