I have talked to you before and you have an early speed density FI unit like I have as I recall (early IROC, no MAF sensor). Now, I'm only guessing based on my experience:
The surging when you come to a stop could be a problem with the speedo not telling the FI that the vehicle is stopped. You should have a yellow and purple wire connector conversion device on your trans where the original speedo cable connected. The two wires go back to the ECM and tells the ECM if the vehicle is moving or not. The solid wire speedo cable wire is also connected to this electronic device and goes back to your speedometer as originally configured. Now, I think you may have changed the original speedo unit to an electonic one, but that doesn't change things and still means you must have input from the trans via the 2 wires to the ECM. The other problem I had with mine, which kind of sounds like your surging problem, (mine would stall, not surge) was a fuel pressure problem. Not enough fuel at a constant pressure. Put a gauge on your fuel pressue and see when you gun it that it holds the pressure. It should hold about 42 lbs. There is a fitting on your FI unit rail where a gauge can be installed. I solved my problem with an expensive external Edelbrock fuel pump made specifically for FI. If your fuel pump is in the tank and is a later corvette type for FI, then forget what I just said. All this is guess work, but I want to see all us FI guys succeed.
