sounds like a spun bearing. A perfect opportunity to do a 3.0L swap. Youll pay less than an svt motor, and with the addition of the svt heads, your looking at an extra 20-30 hp and 30 tq.
Pick up a used 3.0L DOHC duratec (NOT vulcan) engine from a 1999 Taurus or Sable which is for the most part the same motor. Its just been bored over from a 2.5L to a 3.0L. youll have to fill one of the oil passages with some jb weld and shorten the crank on the timing cover side. Its not to hard of a job to do. Ive swapped mine out with a 3.0L along with numerous others over on
www.contour.org. Any other questions feel free to ask!