Resistor in IAT (Intake Air Temperature) sensor circuit. Here's a dyno test from Zetec forum that suggests no improvement:
http://www.contour.org/forums/ultimatebb.php?ubb=get_topic;f=33;t=000777
Search: IAT > Zetec > subject, will get you a few hits with opinions. Your duplicate post also noted.
98 Mystique LS v6 atx 110,000km
97 Contour LX v6 atx 125,000km
stock CD on LS, cass on LX
spoiler, tinted windows on LS only
4 wheel discs on LX only
All other available options on both
| 
