6.4. System of ignition

General information
The electric equipment of the engine includes the rechargeable battery, system of ignition (high and low voltage), a starter and the generator.
For search and definition of malfunctions in system of the electric equipment of the engine it is necessary to use diagnostic schemes.

Ignition distributor
The chain of ignition consists of the rechargeable battery, the distributor of ignition, the switch of ignition, spark plugs and wires of low and high voltage. Information on the rechargeable battery is provided in the corresponding chapter.

HEI ignition distributor
The distributor of ignition is equipped with the internal sensor consisting of a permanent magnet, a polar tip with internal teeths and the reading-out coil. Teeths of the core of the breaker rotate in a polar tip. When teeths of the core of the breaker coincide with teeths of a polar tip, in the reading-out coil tension which is a signal for the electronic block on shutdown of current in primary chain of the induction coil of ignition is induced. Primary current sharply decreases and in a secondary winding of the coil of ignition high voltage is induced. This tension through a rotor moves on high-voltage wires to spark plugs. The condenser installed in the ignition distributor provides suppression of hindrances for radio reception.
All changes in the ignition moment in the HEI (EST) distributor are carried out by the electronic module of management (ESM). The module obtains information from various sensors installed on the engine counts the required corner of an advancing of ignition and transmits a signal to the ignition distributor to corresponding change of a corner of an advancing of ignition. In the distributor of ignition there is an auxiliary system of an advancing of ignition for control of the ignition block at refusal of ESM, at the same time vacuum or mechanical systems of change of a corner of an advancing of ignition are not applied.

Ignition advancing corner
When using a stroboscope connect an adapter between a spark plug of the first cylinder and the high-voltage wire going to this candle or use the sensor of induction type. Do not puncture isolation of a high-voltage wire. At emergence of damage to isolation of a high-voltage wire there will be a breakdown on the next detail connected to "weight", and the candle will not work properly. On some engines the opening for the magnetic sensor used in common with the special electronic equipment for installation of the moment of ignition is provided. For data on rules of work with such equipment it is necessary to address instructions of producers.

High-voltage wires
The high-voltage wires applied in system of ignition have the impregnated carbonaceous core surrounded with a cover from silicone rubber with a diameter of 8 mm. The silicone cover maintains very high temperatures and provides good isolation from high voltage in system of ignition of HEI.
The tips of high-voltage wires made of silicone rubber are densely put on candles. Before removal of a tip it needs to be turned on a half of a turn.
Connection of a stroboscope or any other measuring equipment should be made with care.
Do not insert probes between a tip and a wire or through a silicone cover. It is necessary to carry out parallel connections, using an adapter. Do not pull for a high-voltage wire at removal it from a spark plug, and pull for a tip or use adaptation intended for this purpose.

Spark plugs

Fig. 6.14. Example of marking of a spark plug: R – resistive type; 4 – the size of a carving is 14 mm; 6 – thermal mode; T – a conic skirt of the insulator; S – the extended electrode tip

On all engines, except for engines with an aluminum head of cylinders, candles of resistive type with a conic skirt of the insulator are established. At installation of such candles application of laying is not required. The system of marking of spark plugs is presented in fig. 6.14.
The first and the last letters designate concrete type of a candle. Figures specify the size of a carving and the thermal mode.
The first figure designates the carving size:
4 – 14 mm; 2 – conical part 1/2 of inch;
8 – 18 mm; 5 – conical part 1/2 of inch;
10 – 10 mm; 6 – conical part 3/4 of inch;
12 – 12 mm; 7 – conical part 7/8 of inch.
The second figure means the thermal mode:
COLD..... HOT.
Under usual service conditions the engine can work in the mode of idling, slow speed and high speed of the movement. The incidental or periodic movement with a high speed is necessary for improvement of work of spark plugs. At the same time the bigger amount of heat is generated thanks to what burn out the carbonaceous and other deposits which are formed during the frequent operation of the engine idling or at the movement with frequent stops. Spark plugs are protected by the isolating tip made of the special heatresistant material closing the plug of a candle and partially the insulator. Such tips prevent proskakivany sparks on the candle causing interruptions in operation of the engine. It is not necessary to mix the crown category with a proskakivaniye of a spark or short circuit in the insulator.
The crown category is followed by a constant blue luminescence around the insulator. The crown category is a sign of existence of the field of high voltage and does not make impact on behavior of system of ignition. Usually crown category can be seen only in the dark. Such category leads to pushing away of particles of dirt thanks to what on the part of the isolation center which is directly over the case there is a light ring. This ring is mistakenly taken sometimes for the proof of break of gases between the case of a candle and the insulator.

Ignition switch
The mechanical switch of ignition is located in the right part of a steering column under a steering wheel. An electric part is separated from a key and the lock of ignition, however, both parts work synchronously and in common thanks to a connecting bar. The complete description of work of a key and the lock of ignition, and also a connecting bar is given in the head "Steering wheel and a steering column".

Diagnostics of elements of system of ignition

Spark plugs
The burned slightly or polluted candles can well idle, but at increase in frequency of rotation of a bent shaft they can work with interruptions. Unstable work of spark plugs is determined by many signs: to the increased fuel consumption, reduction of engine capacity, reduction of speed, the complicated start-up and unstable operation of the engine in general.
Violation of operability of spark plugs can be also because of adjournment of a deposit, the increased interelectrode gap and the burst insulator. The deposit on candles represents carbonaceous deposits of black color. Emergence of black deposits usually is result of slow driving and frequent stops when the necessary working temperature of the engine is reached seldom. Wear of pistons and rings, the wrong installation of a corner of an advancing of ignition, reenrichment of toplivnovozdushny mix, application of candles with too cold thermal mode – all this also leads to emergence of a deposit. Burning out of an interelectrode gap at a small run usually indicates that the engine works at high frequencies of rotation of a bent shaft, with the big loading which is constantly exceeding normal amounts or that the candle is intended for more high temperatures. Wear of an electrode can also be a consequence of an overheat of a candle as a result of leak of the fulfilled gases through a carving because of an insufficient inhaling of a spark plug. Use of excessively grown poor mixes also results in strong wear of an electrode of a spark plug.
Emergence of cracks in the insulator usually is result of the wrong installation of a candle or adjustment of an interelectrode gap. Destruction of the top insulator is usually caused by application of an inappropriate key or blow. The crack in the insulator can be visible not at once, and after hit of oil or moisture in a crack. Cracks often appear directly under zakrainy cases and can be not visible. Destruction of the lower insulator is usually caused by the wrong adjustment of an interelectrode gap and is, as a rule, noticeable at once. Such destruction can come from a candle overheat at high speeds of the movement or at big loadings. At adjustment of an interelectrode gap it is necessary to turn in only side (connected to "weight") an electrode. Spark plugs with the burst insulators are subject to replacement.


Ignition distributor
The described procedures are applicable in general to the majority of modifications of the car. When in maintenance there are distinctions or additional information, see the head "Service on the car" for concrete modification is required.

HEI distributor
1. When conducting check of a compression disconnect a wire from the ignition switch at the ignition distributor. At a detachment of a wire do not use the screw-driver for an otzhatiya of a locking uvula as at the same time there can be a damage of a wire.
2. Periodic lubricant of the distributor of ignition is not required. Engine oil greases the lower plug, and the tank with oil provides lubricant of the top plug.
3. The plug of a tachometer (TASN) is near the plug of the switch of ignition (VAT) on an ignition distributor cover.

Do not allow short circuit of the plug of a tachometer on "weight" in order to avoid damage of the block and/or the coil of ignition at all. Some of the tachometers operated now can be incompatible with this system of ignition of the high voltage (HEI).

4. Disconnection duration in the distributor of ignition is regulated by the ESM block and cannot be adjusted by technicians.
5. The material used at production of high-voltage wires very elastic therefore such wires maintain higher thermal loadings and tension, but at the same time there are more probable teases and cuts. High-voltage wires need to be laid with care to avoid wear and cuts. At a detachment of a high-voltage wire from a candle it is necessary to turn a wire tip on a candle and to pull for it or to use the special device for removal of tips.

Installation of a corner of an advancing of ignition
1. At the switched-off ignition connect an alarm wire of a stroboscope to a spark plug of the first cylinder. For connection use a separate wire, connecting it to a candle and an alarm wire. Do not puncture a high-voltage wire and do not try to insert a wire between a tip and a high-voltage wire. Connect food for a stroboscope according to the instruction.
2. Launch the engine and direct stroboscope light to a tag for installation of a corner of an advancing of ignition. The tag on the balance weight or a pulley has to coincide with the index. If it is necessary to change an ignition advancing corner, weaken a clamp bolt on the basis of the distributor of ignition and, watching a tag in the light of a stroboscope, turn the distributor until the tag is combined with the index. Tighten a bolt of fastening of a clamp and check installation of a corner of an advancing of ignition.
3. Switch off the engine and disconnect a stroboscope and again connect a high-voltage wire to a spark plug.

High-voltage wires
Remove tips of high-voltage wires from spark plugs with care. For removal turn a tip on a half of a turn then pull for it and disconnect from a spark plug.
When replacing high-voltage wires accurately lay wires, using the corresponding clamps. The wrong laying of high-voltage wires can lead to emergence of a radio noise and the wrong order of ignition or to short circuit of wires on "weight". It is necessary to make replacement of tips of high-voltage wires with extra care. It is necessary to be convinced that the metal plug is completely installed on the plug of a candle and the tip does not move on a wire.
When moving a tip on a wire an impression of dense landing can be made. A good method of check of correctness of landing of a tip is its rocking in the parties. If he is put densely, the strong resistance to rocking will be felt. In case of insufficiently dense contact of the plug of a wire and the plug of a spark plug resistance to side shift will be caused only by rigidity of the tip.

Service on the car

System of ignition
1. Disconnect a wire from the negative plug of the rechargeable battery.
2. Disconnect central and high-voltage wires from an ignition distributor cover.
3. Disconnect sockets from the coil of ignition and EST.
4. Turn out both nuts of fastening of an arm of a cam of the distributor of ignition.

Fig. 6.15. Ignition distributor: 1 – ignition distributor cover; 2 – screw; 3 – ignition distributor rotor; 4 – shaft; 5 – stopper; 6 – stopper; 7 – screw; 8 – polar tip and plate; 9 – ignition distributor block; 10 – consolidation of the case; 11 – ignition distributor case; 12 – ring of round section; 13 – spring; 14 – washer; 15 – coupling spring; 16 – coupling; 17 – hairpin; 18 – socket

5. Remove the distributor of ignition (fig. 6.15). Mark shlitsevy the drive and a camshaft for the correct repeated assembly.
1. Install the ignition distributor. Expose the drive to Shlitseva according to earlier put tags.
2. Screw nuts of fastening of an arm of a cam of the distributor of ignition.
3. Connect sockets to the coil of ignition and EST.
4. Connect central and high-voltage wires to an ignition distributor cover.
5. Connect a wire to the negative plug of the rechargeable battery.

Ignition coil
1. Disconnect a wire from the negative plug of the rechargeable battery.
2. Disconnect the socket from the ignition distributor.
3. Disconnect the central wire.
4. Turn out bolts and remove the ignition coil.
1. Install the ignition coil.
2. Fix by bolts the ignition coil.
3. Connect the central wire.
4. Connect the socket to the ignition distributor.
5. Connect a wire to the negative plug of the rechargeable battery.

Electrical wiring of a motor compartment
General information

Fig. 6.16. Electrical wiring of a motor compartment

The electric equipment of a motor compartment includes the rechargeable battery, system of ignition (high and low voltage), a starter and the generator with the corresponding wires (fig. 6.16).
For definition of concrete malfunction it is necessary to address the corresponding chapter of this manual.