Just out of no where driving down the highway my 2004 Chrysler Pacifica sounds like a lawnmower and seems to not want to get up and go.... not leaking any fluids.... no check lights came on.... just had an oil change a month ago.... 120000 miles..... what on earth could this be?? When I start it up is sounds like a beast for a few seconds then a lawnmower... very hard to describe, but lawnmower is the best description!