Distributor system (E7J engine)
The E7J engine is equipped with a distributor; in addition, the ignition system includes an amplifier module, one ignition coil, a speed/crankshaft position sensor, and a knock sensor.
Depending on the information received from various sensors, the electronic control module calculates the ignition timing / ignition coil supply time that is optimal for a certain engine speed and load, the ECU switches the amplifier unit, controlling the primary (low voltage) ignition coil circuit. This leads to a high voltage in the secondary winding, which is then distributed through the HV wires to the corresponding spark plug.
The distributor is attached to the left end of the camshaft. Note that its position has no effect on ignition timing, high voltage current is transmitted from the ignition coil to the spark plug. The ignition timing signal is fully controlled by the electronic control module.
A knock sensor is installed on the cylinder block, which informs the electronic control module about the start of "detonation" engine. This device is sensitive to a certain frequency of vibration, thus detecting knock pulses during early ignition. The knock sensor sends an electrical signal to the electronic control module, which reduces the ignition timing until it stops "detonation" - the ignition timing is then gradually returned to "normal" values. In this way the ignition timing is kept as close as possible to the knock threshold - the most efficient setting for the engine under normal operating conditions.
System without distributor (K7M, F3R and F7R engines)
The K7M, F3R and F7R engines are equipped with an ECU controlled distributorless ignition system that simply consists of two BB ignition coils, a crankshaft speed/position sensor and a knock sensor. Each ignition coil serves two cylinders (one feeds the spark plugs for cylinders #1 and #4, and the other feeds the spark plugs for cylinders #2 and #3). Ignition coils work on the principle "idle spark", that is, the spark in the spark plugs jumps twice for each engine cycle, on the compression stroke and on the exhaust stroke. The electronic control module uses signals from various sensors to calculate the required ignition timing and ignition coil feed time. The functioning of the knock sensor is described above - note that on F3R engines it is mounted on the cylinder head.
Precautions
To prevent damage to ignition system components and reduce the risk of injury, the following precautions must be observed.
- a) Turn off the ignition before disconnecting the system wiring.
- b) Before connecting or disconnecting any diagnostic equipment (e.g. stroboscope) check that the ignition is off.
- With) Do not short to ground the primary or secondary circuits of the ignition coil.
Warning! The voltages generated by a non-contact ignition system are significantly higher than those produced by a conventional ignition system. Be extremely careful when operating the system with the ignition on. People with implanted cardiac pacemakers should not touch ignition circuits, components, or diagnostic equipment.