Hey all,

I recently started over with my 383. I used stock AWSY (Originally AKWH) as a base, then updated for 90# injectors and disabled EGR. I have done one tuning run for the VE table and it probably needs a few more to get it right. It idles pretty smoothly at 700 RPM with IAC counts around 5 when warmed up. The issue I am seeing is that when I let off of the gas pedal and coast, I can feel the engine surging as it's decelerating with the transmission in gear. It's soft but noticeably in 4th and stronger in 3rd. I will go to neutral after 3rd until I come to a stop, then the RPM will drop suddenly, almost die, then come back to normal idle. It has only actually died once, but fired right back up.

I have read that a lean condition during deceleration will cause surging. I have tried changing some of the DFCO parameters to keep from pulling too much fuel or introducing more air but they haven't helped. This morning I disabled DFCO entirely but it still hasn't helped. Does anyone have any other ideas of things to look at to eliminate the surging and smooth out deceleration?