Models 1993 and 1994 issue
On models 1993 and 1994 issue a SOHC engine is installed, equipped with an electronic ignition system, consisting of a distributor, a camshaft position sensor placed in it, a power transistor, an ignition coil, a resistive-capacitive assembly and connecting electrical wiring for explosive and LV circuits.
The camshaft position sensor provides reference signals to the on-board processor, which performs general control of the functioning of the ignition system. Based on the information coming from the sensor, the PCM determines such critical engine parameters as its rotational speed and the position of the pistons in the cylinders and calculates the required moment and duration of operation of each of the fuel injection injectors. The camshaft position sensor consists of a rotor plate and a set of light and photodiodes. The sensor generates a sinusoidal signal. Based on the analysis of the characteristics of this signal, the PCM generates commands to control the functioning of the ignition system. The power transistor is used to amplify the ignition signal generated by the processor and to instantly ground the primary circuit of the ignition coil, the secondary winding of which at that moment generates an HV signal sent through special heavy gauge wires through the distributor to the spark plugs.
The PCM receives many signals from various sensors and, based on the analysis of the incoming information, through the power transistor and the ignition coil, controls such parameters as the distribution and ignition timing (see Chapter Engine management systems).
Based on the signals from the knock sensor, the PCM also monitors the ignition efficiency of the air-fuel mixture, adjusting the ignition timing as necessary. The use of a knock sensor allows the system to maintain the ignition timing at the maximum level, thereby providing optimal conditions for the operation of the power unit and allowing you to achieve the greatest efficiency from the engine with minimal fuel consumption.
BB spark plug wires use a carbon conductor enclosed in a rubber insulating jacket and an outer silicone protective tube. Wires of this design are able to withstand high temperatures, while providing reliable insulation of the conductor through which the HV current is passed. Silicone lugs provide a tight fit for the BB wire terminals on the spark plug shanks. Before disconnecting the wire from the candle, turn the tip half a turn (see Chapter Settings and ongoing maintenance).
Models since 1995 vol.
Starting in 1995, Nissan Maxima cars began to install a direct ignition system that works without a distributor. The system consists of six individual coils connected directly to the respective spark plugs. The PCM determines the firing order based on signals from the camshaft and crankshaft position sensors. In addition, the control module constantly receives signals from a number of other information sensors that continuously monitor the operating parameters of the engine, and, based on the analysis of incoming data, develops optimal ignition timing settings.
The system also includes a knock sensor, which allows the PCM to maintain the optimum ignition timing.