That for the reply. When it happens the engine rev's don't climb as the accelerator is pressed. I'm not a mechanic but it's almost like the throttle position just stops moving in the middle part of the pedal travel until passing gear is activated. It will act like this for days at a time and then act normal for a period. I can't find a trend to when it happens (cold temps, first startup, etc.). I'm stumped, but for what this cost I would like consistent performance. At times, merging on the highway has been more exciting than it should have.