GM Cadillac Deville_Fleetwood_ELD_Seville 1990-1998

General Information


3.0L Engine

To provide engine performance, fuel economy, and control of exhaust emissions, the Powertrain Control Module (PCM) manages the functions of the ignition system by analyzing sensor inputs and making appropriate compensations.


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Fig. Ignition Control System-4.6L engine

The 4.6L Northstar ignition control system does not use a conventional distributor or a single ignition coil. In this ignition system, both ends of the four ignition coils are connected to a spark plug. Each coil is connected with spark plugs on companion cylinders, i.e. 1-4, 2-5, 6-7, 3-8. One cylinder is on its compression stroke when the other one is on its exhaust stroke.

The 4.6L Northstar ignition control system controls the fuel combustion by providing a spark to ignite the compressed air/fuel mixture in each cylinder at the correct time.

The PCM controls spark advance and fuel injection for all driving conditions. The PCM monitors input signals from the following components as part of its ignition control function, to determine the required ignition timing:

Ignition Control Module (ICM)
Engine Coolant Temperature (ECT) sensor
Transaxle Range (TR) switch
Throttle Position (TP) sensor
Vehicle Speed Sensor (VSS)
Knock sensor