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Ignition System - general information and precautions
The ignition system is to ignite when the time supplied to the combustion chamber of the engine air-fuel mixture. This task is performed by generating high-voltage electrical arc between the electrodes screwed into each of the cylinders of the spark plugs.
Models 1993 and 1994 Vol.
On models 1993 and 1994 Vol. mounted engine SOHC, equipped with an electronic ignition system consisting of distributor, placed in a camshaft position sensor, the power transistor, the ignition coil, an RC assembly and connecting electrical circuits explosives and drugs.
Camshaft position sensor provides reference signals to the on-board processor, carries out general management of functioning of the ignition system. According to information received from the sensor PCM determines the critical engine parameters such as the frequency of rotation and the position of the pistons in the cylinders, and calculates the required time and duration of the operation of each injector fuel injection. Camshaft position sensor consists of a rotor plate and a set of light and photodiodes. The sensor produces a sinusoidal wave form. Based on the analysis of the characteristics of the PCM signal generates control commands the operation of the ignition system. Power transistor to boost the signal generated by the processor and instant ignition grounding the primary circuit of the ignition coil, the secondary winding is at this moment produces explosives signal sent by a special heavy gauge wire through the distributor to the spark plugs.
PCM receives a plurality of signals from the various sensors and based on analysis of the information received through the power transistor and the ignition coil manages parameters such as distribution and the ignition timing (see chap. Engine management).
PCM based signals from the knock sensor also controls the efficiency of ignition of air-fuel mixture, adjusting as necessary the ignition timing. Using the knock sensor allows the system to maintain the ignition timing is at the maximum level, thus providing optimal conditions for the operation of the power unit and allow to achieve the most efficient return on the engine with minimum fuel consumption.
The explosive spark plug wires used carbon wire encased in rubber insulation jacket and an outer silicone protective tube. Wires of this design are able to withstand high temperatures, while providing a reliable insulation conductor through which a current is passed BB. The silicone tips provide tightness planting explosives wire terminals on the shank of the spark plugs. Before disconnecting the wires from the candles should be on a half-turn to crank the tip (see chap. Adjustment and routine maintenance).
Models from 1995 MY.
Since 1995, for vehicles Nissan Maxima began to establish direct ignition system that works without a distributor. The system consists of six individual coils that are connected directly to the corresponding spark plugs. PCM determines the firing order on the basis of signals from the position sensors distributive and cranked shaft. In addition, the control unit constantly receives signals from a number of other information sensor continuously monitors the operating parameters of the engine, and on the basis of the analysis of the incoming data, generates the optimum ignition timing.
The system also includes a knock sensor that allows the PCM to maintain the optimum value of the ignition timing.
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