Ignition System

Step by step guide on how an automotive engine ignition system works. This article pertains to all internal combustion engines.

Step 1 - Every internal combustion engine must utilize an ignition system which is used to ignite the fuel air mixture inside the combustion chamber.

Engine Ignition System Action Cut-Away

Step 2 - An ignition system starts by referencing the crankshaft while in motion, this rotation produces electrical impulses which are sent to the car's computer for translation.

Crankshaft Angle Sensor

Step 3 - A sensor is used at the rear of the crankshaft also to measure crankshaft flex while making further adjustments.

Rear Crankshaft Positioning Wheel

Step 4 - Camshaft angle sensors are used to give feedback data to the computer to also help with ignition timing.

Camshaft Angle Sensors

Step 5 - This feedback data is transferred the computer via the wiring harness.

Wiring Harness


Written by
Co-Founder and CEO of
35 years in the automotive repair field, ASE Master Technician, Advanced Electrical and Mechanical Theory.


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Article first published (Updated 2015-01-11)