Quote Originally Posted by 1project2many View Post
If Decel surge continues, try reducing spark advance by 2-3 degrees in the cells affected by decel.
Thanks for this. I guess I was wrong - the decel surge is still there although it seems to be a little softer. Now I'm wondering if there is an IAC problem that could be related. Most of the time it will idle at or near target idle speed (650 when warm), but it will occasionally idle higher. I drove it 45 miles at highway speed a few days ago, at the end it was idling over 1000. Shut it off and restarted a minute or two later and was back to normal. IAC sticking? I have a spare IAC that I'm going to swap in to see if anything changes.

If IAC does not solve problem, I will try the timing reduction in the affected cells - thanks!