I install est malloy marine distributor with marine est coil,i try to connect rpm wire when the engine running ...when two gay wire connect together (0ne from coil other one on system wire) the engine stop right away would any one help me my old sytem thunder bolt 4.thanks

Purple wire to "BATT", grey wire to "SENDER", black wire to "GND"
BUT, that's using Mercruiser Thunderbolt IV. Now go in the instructions for your replacement system and make the needed changes.