Help us help you. By posting the year, make, model and engine near the beginning of your help request, followed by the symptoms (no start, high idle, misfire etc.) Along with any prevalent Diagnostic Trouble Codes, aka DTCs, other forum members will be able to help you get to a solution more quickly and easily!
Just putting this out there cause I feel it is a very wierd problem I had this truck in my shop when you put it in gear it would repeatedly bang in and out of gear the traction control light would come on abs light and engine light the code was a u0101 you would have thought that the transmission was going to drop out on the floor. In park or neutral it would purr like a kitten no noticeable misfires at all. Now to uncover the mystery it had seven cheap ass coils in it and on the passenger side is where the can bus lines run apparently one of those coils was misfiring because when I switched all those coils to the driver side it came up with a p0308 which is number 8 misfire this happens on 2006 to 2010 only the Ford explorer for the Ford explorer sport Trac with the V8 engine. We sold the customer for coils for the passenger side of the vehicle and now the transmission shifts like a jewel and the vehicle runs perfect.