I have a brand new 2010 Ranger XLT 4.0L V6 with 3000 miles on it. Here is my problem...
At any time (warm or cold) when it feels like it... it will light all the lights on the computer display panel in the dash and stall or stumble the engine. Usually while applying a slight pressure to the accelerator. If I catch it and back off the accelerator I can prevent a stall and after 2-3 seconds all the lights on the dash go out and everything returns to normal. If it stalls I can restart after lights go out. This has happened with increasing frequency 8-12 times in four months I have owned it.
I took it into my dealership and they say there is NO fault code in the computer and the serviceman cannot duplicate the problem. They had the truck 1 week and he even took it home with him and put 450 miles on my brand new truck with "No Trouble Found"
2nd problem happened on the way to the dealership. I was accelerating on a freeway on-ramp, as it was shifting through the gears (automatic 5 speed OD) it went into neutral between 4-5th gear while I was practically on the floor accelerating. Non the less it caused the engine to over rev, causing me to back off the accelerator. It then clunked into 5th and I was back on the accelerator. This problem did cause a over rev fault code in the ECU.
I don't know if the problems are related to the computer? The dealership asked if I would authorize a removal of the "Ford Factory Security System" as they wanted to try something. I now have it in a box behind my seat. I am hoping this resolves the problem, but I have no confidence in all this computer/ fly by wire crap they are using now.
Caused me to buy the Extended Warranty to 7/75K for $2200!