I have a 2003 AWD V6 Mercury Mountaineer that quit moving. Was driving it then it started acting like it wouldn't pull. Coasted into a parking lot and stopped. Now it won't move. Can move shifter (automatic) but it won't engage a gear (forward or reverse) so can't drive it. While sitting in the parking lot trying to get it in gear the motor seemed sluggish. Sorry, not sure how else to say it. Any ideas?
If when in gear, the engine accelerates(revs) like it is in park or neutral, it sounds like a transmission concern. Have you checked the transmission fluid, running in park? Verify that the level is full, and also take a sniff. If it smells burnt, and is off color(brown), it could indicate an internal problem.