I have to write this story because I believe there could be many people having this same problem due to a very minor issue. CHECK THAT THE LID TO YOUR AIR FILTER BOX IS PROPERLY ATTACHED. MAKE SURE THE TECHNICIAN DOES NOT CUT CORNERS BUT REPLACES THE AIR FILTER LID PROPERLY!
I watched the Ford technician change the air filter in my 2011 Ranger in November 2013 while doing a routine oil change. I watched him struggle to replace the plastic lid on the air filter box. I thought nothing of it at the time!
The truck started to buck in the now seasonal bad weather. This was the first winter I owned the truck and I was disappointed that a new truck would act this way. I took it to the dealer complaining of transmission / overdrive / shifting problems because it felt like the transmission was violently changing gears haphazardly. There was no error code registering and no problem with the o/d software. I was sent home frustrated with one of those "intermittent" problems that you can never replicate when someone is watching. Over the winter months of 2013/2014 (bad winter) I asked every mechanic I knew for ideas and I scanned the internet for ideas. The missing/bucking was so maddening that I was about to trade the Ranger in for a Toyota.
Finally, It was not until I was driving on a nice clear sunny day that as I drove through snow blowing across the fields that the bucking happened regularly when I hit the blowing snow - clearly indicating that blowing snow was the culprit!
I found the article "Help! 2000 explorer 4.0 SOHC Misses/Bucks/Booms/when driving in blowing snow" in this blog that was my god-send. That article explains very well the same problem I had and reminded me of the Ford technician changing my air filter. I immediately popped the hood.
It seems that the technician was too lazy to remove the clamp around the hose that goes from the air filter lid to the intake to free the lid to be put back properly. Instead he forced the lid back on the box by compressing the hose and sliding the lid across the box and under the retaining tabs. The lid was in place, but not entirely engaged under the retaining tabs.
I saw snow crystals where the snow was getting in bypassing the filter and apparently striking the MAFS. I can vouch that when snow crystals hit this MAFS, it feels like you are losing your drive drain or someone is grabbing your engine and stopping it for a fraction of a second! I could not believe the violent effects on the engine due to a small amount of snow getting past the air filter.
All this time I thought I had major drive train problems when in fact it was a minor air (snow) leak!
Read the other posting . . it is very good.
If any oil change technicians read this posting, I would ask you to take the time to replace the lid properly by relieving all the clamps rather than cutting corners.