Ignition System (Gasoline Engines) — Description (Peugeot 406)

On all models, the ignition system is integrated with the fuel injection system and is an integrated engine control system from a single ECU.

On engines with a volume of 1.6 liters, the ignition system consists of 2 ignition coils. Each ignition coil actually consists of 2 separate high voltage windings that supply a spark to two cylinders each (one to cylinders #1 and 4 and the other to cylinders #2 and 3). The ignition pulse is applied to two spark plugs at once for each engine cycle, one on the compression stroke, one on the exhaust stroke (the ignition spark on the exhaust stroke has no effect on the operation of the engine and is therefore wasted). The ECU uses inputs from various sensors to calculate the required ignition timing and ignition coil storage time.

On engines with a volume of 1.8 and 2.0 liters, the ignition system consists of 2 amplifier modules and 4 ignition coils. Each ignition booster unit controls two ignition coils aligned with the spark plugs and mounted directly to the spark plugs, one coil per spark plug. This eliminates the use of high voltage wires. The ECU uses inputs from various sensors to calculate the required ignition timing and ignition coil storage time.