Most cars use high voltage wires, the task of which is to transfer electric current from a coil or ignition module to candles. Just like the rest of the car, during operation, they can fail. Electrical and electromagnetic interference occurs as a result of a mismatch in the quality of the car wire to the specified parameters. They have a negative effect on electronic devices, without which it is difficult to imagine modern machines. The engine is also hit due to improper electronics.
What you need to know
To eliminate the interference, a special protective treatment of high-voltage cables is used. There are basic rules, compliance with which guarantees the receipt of quality products:
- the current flow should be only from the coil;
- from the tip of the candle and to the coil itself there should be no slightest leakage;
- low resistance;
- resistance to sharp temperature fluctuations;
- resistance to environmental influences and chemicals.
It should be noted that the choice of cable should be carried out in accordance with the equipment of the machine. Equally important is the regular replacement of high voltage wires , especially those connected to electronic systems. The occurrence of voltage leakage is possible at the slightest malfunction, because of this, the degree of toxicity of exhaust gases increases and the quality of engine operation deteriorates.
Reasons for the malfunction
Among the main breakdowns, insufficient voltage in the spark plugs has become most widespread. It can occur for several reasons:
- lack of contact between high voltage cables and candles;
- exceeding the established level of resistance;
- low-quality insulation contributing to voltage leakage;
- line break under the insulating layer.
If the high-voltage wires of the VAZ are broken, the voltage level decreases and an electromagnetic pulse occurs, which prevents the transmission of the rated voltage to the candle. As a result of damage, a malfunction occurs in the cylinders caused by delayed ignition, as well as interruptions in engine operation and incorrect response of important automotive sensors.
How to check high voltage wires on a car
In order to identify a damaged wire, you will need a conventional multimeter, which is necessary to check the ignition line. It is recommended to check if the sensors and motor are at idle unstable. This device allows you to determine the level of resistance and identify a damaged line.
Cable resistance can be different, it is selected depending on the engine and manufacturer's recommendations. If the slightest discrepancy is found, the line must be replaced.
Before checking the high voltage wires with a multimeter, it is necessary to inspect them for chips, melted areas and other damage. Cable breakage is a common situation, it often occurs as a result of touching engine parts that are hot to high temperatures or when carrying out inaccurate repairs. Also hit negatively on the surface of chemical aggressive substances.
Verification Steps
On the contact part of the cables there should be no traces of the oxidation process and soot. Do not forget about checking for gaps under the insulating layer. To identify weaknesses, you need to inspect the line with the engine running. If present, sparks will occur at disconnected points. For a more accurate check, it is recommended to turn off the lighting in the garage or to carry out work in the evening.
Before checking the cables with a multimeter, they must be removed. To make the installation of high voltage wires easier, it is recommended to remove each line individually and immediately fix it in its original place.
On the device, the resistance diagnostics mode is selected, a range of 10 kOhm will be the best option. The gap is determined by the absence of the slightest resistance in the cable. Such a product does not fulfill its tasks and must be replaced. The average cable resistance parameter is about 5-6 kOhm.
Voltage level
As noted earlier, the voltage directly depends on the ignition system used in the car and the make of the car. Its value can be in the range of 30-50 kV, as a rule, this parameter is indicated on the product itself. It is worth noting that the VAZ-2110 high-voltage wires included in one set should have a similar nominal resistance, with a difference of no more than 2 kOhm. If this parameter is exceeded, it is recommended to replace the entire kit.
Features of choice
The fundamental factor in choosing is not only the manufacturer and brand of cables. No less attention requires a motor model. This is due to the fact that when replacing and repairing wiring, some features that depend on the manufacturer must be taken into account.
The next criterion is the voltage limit of the wires. If this parameter is exceeded, the line may fail due to breakdown of the insulating layer. It is also worth paying attention to the materials used in the manufacture. They should be distinguished by sufficient ductility, resistance to active chemicals and high temperatures.
If the high voltage wires (“Lanos”, for example) turn out to be completely serviceable, it is necessary to look for the reason for the changes in the motor operation in other elements of the system. First of all, it is worth inspecting the ignition coil and spark plugs.
Current
Current leakage can occur for various reasons, the most common are the following:
- damage to the outer layer;
- malfunction of the ignition coil and cable caps;
- dirt on the distribution cover and wiring.
All this contributes to the deterioration of the dielectric properties of the parts necessary for the operation of the car.
External factors
High voltage wires are constantly exposed to negative effects that reduce the period of use, including:
- Precipitation contributes to the formation of a variety of deposits on the ignition nodes. They increase the likelihood of leakage, providing a conductive effect. Subsequently, the voltage level decreases due to a damaged outer layer.
- Temperature mode. When exposed to high temperatures, the integrity of the caps of the spark plugs, which are located next to the heated elements of the motor, is violated.
- Vibration effect. During operation of the car, vibration occurs that affects the contacts of the lines.
- Low temperature leads to a decrease in ductility of the wires, which increases the likelihood of damage to the caps and insulation.
What you need to pay attention to
Of particular importance when buying is the information that displays the brands of motors to which this product fits. On machines in which high-voltage pulses are generated with a minimum energy value, cables with high distributed resistance cannot be installed. If this rule is not observed, the power of the spark decreases, and as a result, partial ignition of the fuel occurs.
Using a tool such as a tester, you can easily determine the cable resistance level. An exception is the high-voltage wire for cars, which has a special wrap, due to variable values of resistance in the engine.
The material used to make the insulation layer is selected depending on the required characteristics. Also, the correspondence of the voltage level of the ignition system of the car and the selected products is taken into account. In the instructions for the operation and repair of any vehicle, the limit value of the voltage that the cables must withstand without violating the integrity of the insulation is noted. The best option would be a cable, supplemented with caps and insulation from materials that are not exposed to temperature influences (for example, silicone). In addition, it reduces the likelihood of current leakage due to the fact that it does not absorb liquid.
Change engine performance
High voltage wires together with caps must be systematically cleaned of moisture and contaminants, having previously been removed from the motor. Ignition coils, spark plug insulators and the distributor cover also require regular cleaning.
Damage to insulation can not only be seen, but also heard. In the dark, after raising the hood, sparks will become noticeable, which are accompanied by clicks. Often there is a glow near the ignition system devices, the cause of this is a leak of electricity and an increased level of humidity.
The engine at high speeds begins to change if the wire is unsuitable in a non-metallic conductive core. The sound changes, and the motor begins to “troit”. In this case, we can talk about damage to the cable going to the candle. If the engine starts to stall, carefully inspect the center wire.
Varieties
The design of high - voltage wires includes caps, metal contacts, a protective coating and a conductive core. Also in the manufacture are used combs necessary for collecting cables into bundles. Conventionally, products are divided into several types, depending on the characteristics of production and the materials used.
High-voltage wires coated with PVC and stranded copper sheath belong to the first category. The second type is products whose protective coating is made of polyurethane. The most technologically advanced and modern option are cables with silicone insulation and a conductive core, for the production of which Kevlar, polymer or fiberglass material is used. They prevent the occurrence of losses in the ignition system and maintain the required level of breakdown voltage, thus optimizing fuel consumption, increasing the power of the power unit and sparks. It is also worth noting environmental friendliness and resistance to external influences. Products of each category are manufactured in accordance with technical standards and are selected depending on the required characteristics and budget.