Contour Enthusiasts Group Archives Forums Modifications Duratec Maintenance Shaky low end

Make sure the spark plugs your using are Motocraft or Autolite double platinums. The duratec doesn't like other kinds of spark plugs, and causes this problem.

i have checked many times both the wires and plugs, just the other day i found some vacuum hoses that were cracked rather extensively and replaced them but it really had no effect on this problem