Jstreet,
The "cells" are the long term correction values that are stored in NVM when the closed loop learning is enabled. The table you explain that "applies" the adapt values is different in Harley software. The table is a percetage of a "nearby cell" value that would be applied to a "calibratable" cell number.
They are stored in a speed vs. load map. There are other tables that allow when and how much of a "near" cell is used in open loop. Typically the way those values are applied is if the "cell" value that would be used in open loop is adding fuel, the value will be applied. If the cell value is "removing" fuel, the value will ignored. It is safer to be too rich as opposed to too lean in open loop. And that is the way most folks use the long term memory correction to be applied during open loop.

And just as I'm sure Ford software does not allow "learn" during all facets of closed loop, there are instances when the system may be closed loop, without enabling the long term correction. So learning only happens when the engine is in "normal" operation. ( specific sensor inputs must be within a window to allow full learning!)

Does your software have a similar function?

 

I'm not sure about the limitation of other sensor input, since I have no way of datalogging that. I do know that in stock form Ford has that table setup so that it only learns at idle, and just off idle, then all other cells get values applied from those cells. Most tuners I know modify that table so that learning takes place in a broader range.

 

I read it is not 1 to 1 ratio. I.E.) add 6-8% fuel in closed loop, the impact on the fuel mixture from the long term fuel trim, more commonly known as the AFV or adaptive fuel value in open loop is 3-5%.

 

My (limited) understanding is that the bias applied to the O2 sensors with a Xied is very similar to just adjusting the CLB (closed loop bias) tables values to the max (about 850). However, when you do this using a SEPST or similar you don't leave it at that, you also do a bunch of Smartune runs to correct the VE tables accordingly, which then has the knock-on effect of adjusting open loop values, though this can't be inspected with a SEPST.

So, a Xied does a one-off shift of the closed-loop AFR to richer, about 0.5:1 or so, which is good for reducing temp at idle and cruising speed but it does little or nothing for performance, which for many of us is kinda the point of doing a stage-1.

 

Foxster,Where the SERT software changes the CLB ( closed loop bias) the XiED modifies the O2 sensor signal! It sends an incorrect voltage!
And while the "affect" may be similar to "just changing the CLB", it's impact on fuel control function and more importantly, Diagnostics, are not the same! Where the SERT modifies the actual ECM CLB value, closed loop still functions as designed. The "incorrect" O2 value can and does impact and set diagnostic codes, and the signal for fuel control is affected! Fuel control being the actual way in which the pulse width is switched to maintain Stoich ( or biased A/F ratio).