I recently have been having a problem with my car. Every once in a while, the tach will show half the actual rpm's, and the check engine light will come on. I checked the codes and they were 223 (Dual Plug (DPI), SPOUT or IDM circuit fault) and 224 (Failure in ignition coil primary circuit). When this happens, the engine runs fine, no loss of power or anything. I am figuring it has something to do with the DIS module or one of the coil packs. I am just looking for some input on the problem while I try and trace the problem. btw it's a 92 dual plug 2.3 motor. Any help would be greatly appreciated.