So I have a TBI conversion in a Malibu wagon with a 383 I am in the process of tuning. The issue I dont really know where to look to fix is when I am coasting down to a stop {Auto trans) I can hear the idle is surging up and down, up and down. However when I actually get to the stop, it idles fine. I dont think it is a cam surge issue (213/219 114 centerline) but I guess I cant be sure as it also has a little of it going on at very light throttle settings if you hold it in a lower gear. The VE is right on the money even when it is doing this, and the cells around it are as well. I have smoothed out both my VE and timing tables in the areas around these cells. (800-1200 RPM @ 40-50 Map). Suggestions?
Thanks
Roy