[jchambers]

When forced open loop it is always going to be looking at the base fuel table for the commanded lambda once the stabilized operating conditions have been attained (e.g. cold start modifications have expired). This is the commanded lambda that the computer is targeting. For your EEC-V car, the computer won't know where its at hence the need to properly calibrate it. Its going to take the airflow reported from the MAF (simplistically) and then use the commanded lambda from the base fuel table to calculate the desired fuel mass and further calculate the pulsewidth required to arrive at that desired fuel mass. It will not adjust itself. Again, this is where the calibration comes in. Now when you start talking about the Copperhead platform (2011+) the on-board widebands are always feeding back so that the ECM is constantly correcting the fueling. These always operate in closed loop, there is no open loop even under WOT conditions (again ignoring the cold start regime).

Again the point here is to make sure that your base fuel table reflects the commanded lambda that you want to achieve. Then make your MAF corrections so that your actual measured matches this commanded as closely as possible. In theory, if you've done your scaling correctly then your load calculations will be correct and things will be a lot happier all around.