Mitsubishi Eclipse 1990-1998 Repair Guide

General Information


The ignition system on the 1.8L engine uses a pointless type distributor, whose advance mechanism is controlled by the Engine Control Unit (ECU). The distributor houses a built in crankshaft position sensor, camshaft position sensor, ignition coil and ignition power transistor.

When the ignition switch is turned ON , battery voltage is applied to the ignition coil primary winding. As the shaft of the distributor rotates, signals are transmitted from the multi-port injection control unit to the ignition power transistor. These signals activate the power transistor to cause ignition coil primary winding current flow from the ignition coil negative terminal through the power transistor to ground repeatedly. This interruption induces high voltage in the ignition coil secondary windings, which is diverted through the distributor, spark plug cable and spark plug to ground, thus causing ignition in each cylinder.