Contactless ignition systems with distributor
The non-contact ignition system is equipped with models 1.5 l, 1.8 l 1993÷1996. issue., 2.0 l SOHC, 2.4 l SOHC 1994÷1998 issue., 3.0 l SOHC and 3.5 l. The ignition timing in such systems is controlled by a special electronic unit (ECU). On models 1.5 l, 1.8 l, 2.4 l and 3.5 l, the ignition coil and the key transistor are mounted in the distributor housing, on models 2.0 l SOHC and 3.0 l SOHC these elements are installed separately.
When the ignition is turned on, battery voltage is applied to the primary winding of the ignition coil. When the distributor shaft rotates, signal pulses from the onboard processor (PCM) are transmitted to the key transistor of the ignition system, which leads to a periodic short circuit of the negative terminal of the primary winding of the coil (through transistor) to the mass. As a result of such interruptions, an explosive voltage is induced in the secondary circuit of the coil, which is transmitted to the spark plugs of the corresponding cylinders and ensures the timely ignition of the air-fuel mixture in them.
Direct ignition system (DIS)
The ignition system of this type is used on models 1.6 l, 1.8 l 1997÷2000. 2.0L DOHC, 2.4L SOHC since 1999, 2.4L DOHC and 3.0L DOHC. Ignition advance control here, as before, is carried out by the ECU or on-board processor (PCM).
The system includes a crankshaft angle/position sensor (CKP), according to the signals of which the control module monitors the current position of the pistons. By analyzing the information coming from the CKP sensor, the ECU / PCM determines the current engine speed and controls the injection and ignition of the air-fuel mixture in the cylinders. Another component of the system is the TDC sensor, which informs the control module of the passage of each of the pistons of the position of the top dead center of its compression stroke. The information coming from the TDC sensor is used by the module when determining the sequence (and frequency) injection.
When the ignition is turned on, battery voltage is applied to the primary winding of the ignition coil. The signals coming from the CKP sensor are converted by the control module into ignition control pulses and transmitted to the key transistor. The transistor ensures that the negative terminal of the primary winding of the coil is regularly connected to ground, as a result of which a voltage transmitted to the spark plugs BB is induced in the secondary circuit of the coil.
Special precautions should be observed when servicing direct ignition systems:
- a) If the engine does not start, do not keep the ignition key continuously turned to the ON position for more than 10 consecutive seconds;
- b) Make sure that the connection of the tachometer is carried out strictly in accordance with the instructions of the manufacturers - some of the meters produced may not be suitable for use on these models;
- c) In no case do not ground the contact terminals of the ignition coils to ground - the slightest negligence in this matter can lead to failure of the system components;
- d) Do not disconnect the battery while the engine is running;
- e) Make sure the components are properly grounded.