Hello, Thanks to all who respond to posts...I can usually search and find answers by reading responses. This situation is similar to other posts, but I have tried some fixes and no luck so far. My 2010 expedition (183,000 miles) has hesitation and loss of power. I am the second owner as of 101,000 miles and I don't believe the plugs/coils have ever been changed. While driving, sometimes it doesn't want to accelerate very well from a stop. It hick-ups and jerks. I have to pull off the accelerator and press again and sometimes again before it accelerates smoothly. Also while already driving (any speed) if I pull off the accelerator for a moment, and then back on it reacts the same way. I have noticed that if I pull off momentarily and the car seems to be "coasting" and I press on the gas again, it responds by jerking and weak/bogged acceleration. However, if I pull off and wait for "engine brake" where I can hear/feel the engine decelerating, and then I press on the gas again, it responds fine. The other symptom is that I can be out of drive (in 3rd. gear) at 4K or 5K rpm and it accelerates fine with normal acceleration. But the moment I mash the pedal and go WOT, it bogs and does not want to accelerate. I have changed all four oxygen sensors, both VVT solenoids, and the crankshaft position sensor. Last night I put a bottle of Techron fuel system cleaner to see if that helps. I checked to see if the oil from the K&N had migrated to the MAF, but it looked clean. Seems like an air or fuel problem, but could be spark? Thanks for reading...Thanks for responding!!