▁designs ▁were ▁function ally ▁equivalent ▁but ▁slightly ▁different ▁components ▁were ▁used . ▁ ▁Motor ola ▁optimized ▁their ▁design ▁to ▁use ▁as ▁many ▁of ▁their ▁own ▁components ▁as ▁possible . ▁ ▁E EC - IV ▁ ▁Pre lim inary ▁design ▁work ▁in ▁E EC - IV ▁started ▁even ▁before ▁E EC - III ▁was ▁in ▁production . ▁ ▁Over ▁time , ▁there ▁were ▁many ▁different ▁modules ▁designed ▁around ▁this ▁processor . ▁ ▁It ▁is ▁likely ▁that ▁more ▁Ford ▁vehicles ▁were ▁produced ▁using ▁Engine / P ow ert rain ▁Control ▁Mod ules ▁( EC M / PC M ) ▁based ▁on ▁variations ▁of ▁this ▁design ▁than ▁any ▁other ▁module ▁that ▁Ford ▁has ▁ever ▁used . ▁ ▁Un like ▁previous ▁E EC ▁systems , ▁E EC - IV ▁uses ▁a ▁small ▁ign ition ▁module ▁called ▁the ▁T FI ▁or ▁T FI - IV ▁( Th ick ▁Film ▁Integr ated ▁Ign ition ) ▁module . ▁It ▁is ▁usually ▁grey ▁in ▁color ▁and ▁was ▁originally ▁mounted ▁on ▁the ▁distrib utor . ▁Later ▁models ▁have ▁the ▁T FI ▁module ▁mounted ▁on ▁a ▁he ats ink ▁in ▁the ▁engine ▁compart ment . ▁It ▁is ▁pr one ▁to ▁damage ▁from ▁heat . ▁Rep lacement ▁T FI ▁modules ▁are ▁sold ▁with ▁a ▁small ▁packet ▁of ▁heat ▁transfer ▁comp ound ▁which ▁should ▁be ▁applied ▁to ▁the ▁back ▁of ▁the ▁module . ▁It ▁was ▁created ▁with ▁surface - mount ▁technology ▁parts , ▁allowing ▁it ▁to ▁be ▁much ▁smaller ▁than ▁the ▁previous ▁D ura - S park ▁ign ition ▁module . ▁The ▁ign ition ▁co