Ignition System: Description and Operation

EZL System Diagram, (Typical):

PURPOSE
The Bosch EZL ignition system delivers a precisely timed, high energy spark to the combustion chamber to ensure efficient combustion, optimum performance, and strict emissions compliance. The high tension ignition system delivers sufficient energy to ignite the air/fuel mixture under all normal operating conditions.

COMPONENTS
The EZL computerized ignition system consists of the EZL control unit, ignition coil, high-tension distributor, ignition wires with suppression connectors, and spark plugs.

OPERATION
The primary side of the coil is connected with the positive battery terminal via the ignition switch. During the primary current-flow time (coil saturation) the coil is connected to ground through the power output transistor of the EZL control unit (ECU). The ECU receives input signals from the ignition switch, crankshaft position sensor, reference resistor, intake manifold vacuum signal, coolant temperature sensor, throttle valve switch, and the CIS-E control unit; processes these signals, and calculates the appropriate dwell/ignition angle, and simultaneously switches the ignition coil ground circuit.