Idle “hunts” or rolls between 700 and 750 RPM in PARK and 525 to 575 in DRIVE. It creates a lot of vibration that is transferred through my AC lines into my dash. As RPMs increase vibration smooths out.
Yes, this week I performed the procedure you outlined. That is how I got it to run as good as it now does. However, it made little difference to the idle. When setting base idle is it truly "as desired"? I set it as low as I could get a smooth idle from. At least as smooth as this thing gets.
Delco O2 sensor and copper core plugs (CR43TS) installed Nov. last year.
Spark advance always maxes out and eventually starts back at 0 when idling or driving. Is that correct?