94 concorde has problems, last night it began running rough, like a bad plug or something, all of a sudden as I was driving at 30 mph it seemed to shift into neutral, I acclerated but it just revved,for 10 seconds or so. It then shifted back into drive. I pulled off and checked the T. fluid, oil, PS fluid and radiator, ALL was good. On my way home it did it again , I'm driving and it revves like it in neutal, then engages. I made it home but the engine is rough and seems to be missing and losing power. Also it is running at very high RPM's 3-4 and at times almost into the red. Any advice will be apprecited.