Ford 2.3L OHC Dual Plug System,also used by [...] system was introduced in [...] 1989-97 Ford Ranger,1989-93 Mustang and 1994-97 Mazda B2300 [...] system has a dual plug inhibit (DPI) [...] engine start-up,the DPI signal from the PCM to the DIS module is 12 [.... Login to read more.