Take the plug wires back to AutoZone and get either AutoLite Professionals or Motorcrafts.

The knocking might be from the ignition misfires which are being caused by cross-coupling of the firing voltages from adjacent plug wires.

Steve


98 Contour SE Sport 2.5 Duratec ATX The wifey's car 89 Taurus SHO - 246K miles 94 SHO ATX - 190K 1997 F-150 5.4L ATX - The Workhorse 150K. ANY THREAD WITH "OMG" or "WTF" ETC IN THE TITLE WILL BE IGNORED!