Distributor cap is a DSII and can be used on DSI also. Just has an adapter that mounts between distibutor and cap. The strain relief can be different colors, depending on year and system. Here are a few diagrams. "If" the run and start leads are reversed to the module it will do exactly what you are experiencing. Possibily when you replaced ign switch? Color of wire on the blue module can be red and white, just follow the pin locations. "If" buying a module, Motorcraft is best.