Vehicle Ignition Systems Explained

3.8L (3800) Ignition Details

The electronic ignition (EI) system produces a high energy secondary spark. This spark is used to ignite the compressed air/fuel mixture at precisely the correct time. This provides optimal performance, fuel economy, and control of exhaust emissions. This ignition system uses one coil for each pair of cylinders. Companion cylinders are a pair of cylinders that are at top dead center (TDC) at the same time.

3.4L V6 (3400) Ignition System Details

The GM 3.4L V6 electronic ignition system is responsible for producing and controlling a high energy secondary spark. This spark is used to ignite the compressed air/fuel mixture at precisely the correct time. This provides optimal performance, fuel economy, and control of exhaust emissions. This ignition system uses one coil for each pair of cylinders.


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2200 (2.2L) Ecotec Four Cylinder Ignition Deltails

Each pair of cylinders that are at top dead center (TDC) at the same time are known as companion cylinders. The cylinder that is at TDC of its compression stroke is called the event cylinder. The cylinder that is at TDC of its exhaust stroke is called the waste cylinder. When the ignition coil is triggered, both companion cylinder spark plugs fire at the same time, completing a series circuit.

Vortec V8 Trucks Ignition Deltails

This ignition system consists of a separate ignition coil connected to each spark plug by a short secondary wire. The driver modules within each coil assembly are commanded ON/OFF by the powertrain control module (PCM). The PCM primarily uses engine speed and position information from the crankshaft and camshaft position (CMP) sensors to control the sequence, dwell, and timing of the spark.


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