GM Cadillac 1967-1989 Repair Guide

HEI System Tachometer Hookup


There is a terminal marked TACH on the distributor cap. Connect one tachometer lead to this terminal and the other lead to a ground. On some tachometers, the leads must be connected to the TACH terminal and to the battery positive terminal.

Never ground the TACH terminal; serious module and ignition coil damage will result. If there is any doubt as to the correct tachometer hookup, check with the tachometer manufacturer.