Detailed Tips for checking the ignition system.

Try not to crank the engine with the ignition on and at least one high-voltage wire removed!

The fact is that the ignition coil, when the current in its primary circuit is interrupted, creates a voltage in the secondary circuit. It is limited by the breakdown voltage in the candle, i.e. voltage at which a spark occurs.

If removed high voltage wire, then the restrictions high voltage does not occur, and there is a very high probability of electrical breakdown elsewhere, for example, the cover of the distributor. Therefore, check the spark on candles Japanese cars with their delicate electronics it is necessary as follows. Unscrew all the candles and tie them with bare wire, for example, aluminum, in a row. Fasten the free end of the wire to the "mass", i.e. screw to any unpainted part on the engine, and put all the tips on the candles high voltage wires.

Now, scrolling the engine with a starter, you can observe a spark on all the candles. If the spark is very thin (filamentous), it can be argued that the switch has failed. If the candles are dirty and wet, they must be cleaned, but it is better to replace them with new ones. Set the same gaps on the candles. The larger the gap in the candles, the better the combustible mixture in the cylinders will be ignited, but the higher the probability of failure (electrical breakdown) of any elements of the ignition system. Turn the starter 10-20 revolutions.

The spark should jump only between the central and side electrodes (in the same place), be thick, click loudly and be purple. If everyone electrical discharge will at least by some sign differ from the previous discharge and from the discharges on neighboring candles, then it is necessary to look for the reason, because this indicates a malfunction (in this case, the engine may start, but it will work unevenly).

Now set a gap of 2-4 mm on one candle and again turn the engine with a starter. If there is no spark on a candle with a large gap, or it changes in power with each click, then the ignition coil is most likely faulty. Another reason may be that there are leaks in the high-voltage part of the system (cracks, breakdowns, etc.).

Measure electrical resistance wires. It should be about 5 kΩ and not differ by more than 1 kΩ from the resistance of other wires. Although many engines work quite tolerably even with a resistance of high-voltage wires of about 15 kOhm. Very often, the reason for the lack of spark is the failure of the switch.

The quality of the spark on the spark plugs is checked in the same way as in its absence. However, it is desirable to change the gap between the high-voltage wire of the spark plug and the mass. A spark is considered good if it penetrates a gap of at least 7 mm.

A malfunction that occurs as if it does not exist at all, but it is much more difficult to find the cause of its occurrence. An ammeter will not even be able to help in this case. The best way troubleshooting is to turn off one or another device or section of the circuit from the ignition system and try, if possible, to get a spark without them. The appearance of a good spark indicates a malfunction of the switched off device.

When, after checking, it turned out that the spark between the spark plug and the high-voltage wire is weak, the distributor is turned off from the ignition circuit and the quality of the spark between the ground and the high-voltage wire of the ignition coil is checked. The presence of a strong spark indicates that the entire ignition system to the distributor is working, except for the distributor cap, rotor or high-voltage spark plug wires. If these parts are cracked or damaged, they must be replaced.

If, when the distributor is turned off, the spark, as before, is weak, you should carefully check all the clamps of the current circuit low voltage, cleanliness and reliability of fastening. If, even after checking the clamps, the spark is weak, it is necessary to turn off the breaker from the low voltage circuit. Its action can be replaced by an additional wire, one end of which is connected to the connection point of the capacitor wire with the low voltage wire coming from the P terminal of the ignition coil, and the other end is sharply struck by mass. In this case, the wires of the ignition coil and the capacitor must be disconnected from the terminal K of the breaker.

The occurrence of a strong spark between the ground and the high-voltage wire of the coil without the action of the breaker indicates a malfunction of the breaker.

To control the safety and reliability of the contact and isolation of the current-carrying parts of the circle from the mass, you need to check the inner circle of the breaker, the condition and gap in its contacts on all cam protrusions. When checking the inner circle of the breaker, find out whether the cam, bushings of the breaker roller, the axis and the hole for the axis of the breaker lever did not work out, the breaker panel is securely seated on the bearing.

If the spark is weak and irregular when the breaker is off, then the capacitor or ignition coil is most likely faulty. After making sure that the capacitor is working, you should check the serviceability of the ignition coil. Strong heating of the ignition coil indicates a short circuit in the primary winding. Replace the defective coil.

One of the main reasons that the engine does not start when the starter is cranking is the absence of a spark discharge between the electrodes of the candles. This can be especially annoying if you need to leave urgently. We need to look for the "lost". First of all, inspect the wires and devices of the ignition system. If there is dirt, oil or water, they should be wiped with a dry cloth. Then try starting the engine again. It is possible that this will succeed. If not, inspect the high voltage wires. They should not have a "raggedy" appearance and insulation violations. Otherwise, they will have to be replaced. Check the condition of the contacts by simply rubbing the wires with your hand. The following reasons: all spark plugs do not work; faulty ignition coil or breaker-distributor; open or short to ground wires of the low voltage circuit. Let's start the search for a spark with candle wires. To do this, remove the tip of the spark plug wire from the spark plug. Bring the candle wire to the mass of the car at a distance of 5 - 8 mm and turn on the starter for a while.

"Strike" the spark white color

Each contact opening should be accompanied by an uninterrupted white spark with a blue tint, purple, yellow and red sparks indicate a malfunction in the ignition system circuits. If there is no spark, the ignition coil must be checked separately. To do this, remove the central wire coming from the coil from the distributor cap and repeat the spark-cutting procedure. If a spark appears, then the coil is in order, and the fault must be sought in the breaker-distributor. Otherwise, either the coil is faulty or there is an open in the low voltage circuit. If suspicion has fallen on the breaker-distributor, inspect its cover from the inside. If cracks are found, the cover must be replaced. Check the center carbon contact for "hanging" by simply moving it slightly with your finger. It is useful to wash the cover with gasoline.

Apply test lamp

Breakdown of the insulation of the distributor rotor can be checked by placing the central high-voltage wire with a gap from the rotor electrode and manually opening and closing the breaker contacts. If sparking occurs in the gap, the rotor is defective and must be replaced. The low voltage circuit is easy to check with control lamp with a voltage of 12 V and a power of not more than 3 W, which is connected with one contact to the low voltage terminal of the breaker, and with the other - to ground. Set the breaker contacts to the closed position and turn on the ignition. If the lamp is on when the contacts are open, but not when the contacts are closed, then the low voltage circuit is working. If the lamp does not light when the contacts open, then the fault must be sought either in the low voltage conductors or in the primary winding of the ignition coil. If the lamp is on and closed contacts, this indicates a strong oxidation of the breaker contacts, a broken wire from the breaker terminal to the lever, or a broken wire connecting the movable breaker disk to the housing. The oxidized contacts are cleaned, after which the gap is adjusted.

Even on modern cars, equipped with an abundance of electronics and injection units, problems regularly arise. This is due to the operation, and there's nothing you can do about it. Most often, car owners are advised to learn how to check the spark on the injector, because its disappearance leads to difficulties in starting and precarious work motor.

At the same time, it is important to know that checking with your own hands is good, but you can get a strong charge of electricity, ruin the ignition module or controller if you do not know all the intricacies of diagnostics.

spark test

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The ideal result is when a bright blue color comes from the candle. In all other cases, when the color is white, red or another, the system is not all right. The spark must be powerful, confident, appear constantly, and not periodically. The spark should not be pink either.

If there is no spark at all, and the distributor is fully functional, it is recommended to check the candle itself directly. For example, you can install a known-good spark plug instead of a checked one.

On the injector, often, if the engine runs intermittently in XX mode or its power decreases significantly, it is customary to talk about problems with candles. Important Information can issue the Check Engine indicator.

Checking a module with a tester

The module on the injector does not apply to nodes that constantly break or cause trouble. However, in some cases, problems with it are noted. For example, if the winding is damaged, a breakdown of the insulation layer is observed, which ultimately leads to a short circuit. Also, the bobbin (module) can easily fail if the candles or armored wires are faulty.

This is a simple verification option. You need to take a tester, connect one of its terminals to the module contact marked A, and the other end to ground (any part of the car body). Start the engine and look at the tester readings.

1. The module is fully functional if the device shows 12 V.
2. All other values, up to their absence, indicate malfunctions (it is also recommended to check the fuses).

spark color

Thus, the following conclusions can be drawn from the color of the spark from candles.

1. If the color is white with a blue tint, the spark is constant, then everything is fine.
2. If the spark is purple or transparent, colorless, it can be concluded that the module, distributor or armored wires are damaged. Such a spark is knocked out at intervals or appears 1-2 times when checking.
3. Red or yellowish color indicates the presence of additives in the fuel.

Candles

On the appearance sparks, its color, is influenced by the candle itself, its condition.

Table: condition and appearance of candles

Candle condition	Decryption
Normal candle - the color of the deposits on the insulator (the skirt of the central electrode) is light brown or coffee; soot and deposits are minimal. Complete absence of traces of oil. Moderate electrode burnout.	Owner this motor one can only envy, and there is something - this economical consumption fuel and no need to add oil from replacement to replacement.
The central electrode is covered with velvety black soot - dry soot. Typical example candles from an engine with increased fuel consumption.	rich air-fuel mixture- malfunction of the injector - malfunction of the engine management system (for example, failure or incorrect readings oxygen sensor), malfunction of the air damper drive mechanism, clogging of the air filter.
The color of the electrode is from light gray to white.	An example of an excessively lean air-fuel mixture.
The skirt of the central electrode of the candle has a characteristic reddish hue, this color can be compared with the color of red brick.	This reddening is caused by the operation of the engine on fuel containing an excessive amount of additives containing metal. Long-term use of such fuel will lead to the fact that metal deposits form a conductive coating on the surface of the insulation, through which it will be easier for the current to pass than between the electrodes of the candle, and the candle will stop working. Such a plaque on a candle is most typical when using manganese additives in gasoline, which are used to increase the octane number of fuel.
Pronounced traces of oil - black oily soot, especially in the threaded part.	This usually indicates the wrong temperature regime in the direction of insufficient candle temperature or - to hit engine oil into the cylinder. Possible malfunctions: wrong selection candles (too "cold" candle), wear of the valve guides, valve stem seals, piston rings. On the face increased consumption oils. In the first minutes of engine operation, at the time of warming up, a characteristic white-blue exhaust.
The central electrode and its skirt are covered with a dense layer of oil mixed with drops of unburned fuel and small particles from the destruction that occurred in this cylinder.	The reason for this is the destruction of one of the valves or the breakage of the partitions between the piston rings with the ingress of metal particles between the valve and its seat. AT this case the engine "troits" without ceasing, a significant loss of power is noticeable, fuel consumption increases one and a half, two times. There is only one way out - repair.
Complete destruction of the central electrode with its ceramic skirt.	The cause of this destruction could be one of the following factors: long work knocking engine, use of fuel with low octane rating, very early ignition, and - just a defective candle. The symptoms of the engine are the same as in the previous case. The only thing you can hope for is that the particles of the central electrode managed to slip into exhaust system without getting stuck under exhaust valve otherwise, repair of the cylinder head cannot be avoided either.
Destruction of the ceramic insulator.	Causes of occurrence: a sharp change in temperature, for example, when cooling a candle unscrewed from a hot engine, in cold water. In some cases, the destruction may be caused by a defect in the candle itself (marriage or fake), or mechanical damage, for example, as a result of a fall
The spark plug electrode is overgrown with ash deposits, the color does not play a decisive role, it only indicates the operation of the fuel system.	The reason for this build-up is the combustion of oil due to the development or occurrence of oil scraper piston rings. The engine has increased oil consumption, when regassing from exhaust pipe strong, blue smoke, the smell of the exhaust is similar to that of a motorcycle.
Splashing spark plugs with gasoline.	Often occurs due to a malfunction of the injector. In winter, it can occur due to the fact that gasoline that has entered the combustion chamber does not have time to evaporate and settles on spark plugs and cylinder walls.