[RANT] Just remember this too--and this goes for several of you who gave me and others shit trying to help you. Just because some of us don't have 5.0s and have 4.6s doesn't mean we don't know jack shit about these cars, and we don't appreciate some of the attitudes we get sometimes when we fucking try to help out. Ford doesn't know everything either. They can't even help me figure out how to reprogram my goddamn moonroof on my new 2011 MKS to open fully when letting the windows down like it did on my less fancier 2007 MKZ!
That said, take everything on here I have tried to help with a grain of salt. If it helps great, if it doesn't I apologize. I can gurantee you this--no one wants to see these cars break like this and we all want to help figure out the problem. You can take that to the bank.
Tech is knowledge and ideas put together to make something happen or to understand a problem. You will not find a better technical area that where you are right now.
Some of you may or may not know me, but I am one fuckin helluva problem solver, if I do say so myself. I do it for a living. I help make over 100 million 45 nanometer transistors work on a piece of silicon smaller than your thumbnail. The very first thing I do in problem solving is NEVER assume it can't be X. You are just asking to be bit in the ass if you do! Look into all ideas and see which ones fit the scenario best; there may be a combination of causes instead of a single silver bullet root cause. BTW, system problems don't have single root causes. Now I have said my piece, so...[/RANT]
I'd be looking into this "green technology" that Ford has put into play with the Aggressive Deceleration Fuel Shut-Off (ADFSO), because from what I have read on this issue, it sounds like a lot of them are blowing when you lift off the gas.
There is a section of code in the PCM that controlls this ADFSO and I wonder if the tuners are not aware of this. That is why I made the comment: Ever see a circle track race car toast a piston when it runs out of fuel? The fucking piston(s) melt and break because they have no gasoline to cool them!
I remember an old Ford car I had back in the 80s that had a "throttle body injection" system on it. When you would rev it up you could see the fuel spray obviously. However when you let off the gas and let the engine decel, it didn't completely turn off the gas. It would spit ever so slightly in pulses to prevent total fuel starvation.
HTH
Mike