From the technical state of automotive high-voltage ignition wires depends not only on the stability of the engine, and whether it be acquired at all. The main purpose of high voltage wires – to transmit an electrical impulse of high voltage from the ignition coil to spark. In case of rupture of an electric circuit or leakage of current or electrical pulse is not supplied to the glow plug or does something so weak that the generation of sparks between the electrodes becomes impossible or sparking occurs, but because of the weakness of the spark ignition of the combustible mixture becomes more difficult.
Causes and symptoms
Due to temperature changes inside of the engine compartment rubber, plastic or silicone layer insulation wire is subjected to considerable loads, so that the surface of the insulator is covered with microscopic cracks, sometimes even invisible to the naked eye. More likely to suffer spark plug caps located next to the heated engine.
Another cause of a violation of the dielectric properties of the insulators is ordinary dirt often accumulate on the wires and the cap and on the distributor cap or the ignition coil.
Depressurization of the protective cap entails the ingress of moisture to the contacts. As a result, their surface is oxidized, increasing the resistance of the conductor.
Often it happens so that due to the improper installation of additional equipment in the engine compartment rubbing occurs high-voltage wires on the nodes or parts of the engine. Over time the wire insulation gets damaged, and sometimes it comes even before the chafing of the conductor.
Very often we can see when the wires are removed starting with the cap, and pulling out their hand in isolation. This method of handling high voltage wires is fraught with the destruction of the metal conductive core or wire breakage in obuhivka wires with non-metallic conductive core. As a result of the breakage inside the wire between the broken ends of a conductor that an electrical discharge that causes a parasitic electromagnetic pulse.
The main symptoms of faulty ignition cables:
— increase the consumption of gasoline;
— drop in engine power;
— difficult engine start in damp weather;
— unstable operation of the engine at medium and high speeds;
the alarm "Check engine".
Methods of diagnosis
The easiest way to find the leak electric current of power lines is to run in the dark engine, open the hood and look closely at. Violations of the insulating layer will be marked periodically slipped spark. In the case of large current leakage (especially in wet weather or before a thunderstorm) the ignition wires will be shrouded in a glowing blue cloud like Aurora Borealis.
Another way to check high-voltage wires is to use wire cut. Cleaning the ends of the conductor, should one of them attach to the "weight" of the machine, and the second to hold the entire length of the ignition wires, do not forget to examine the protective caps. In the dark in place of insulation damage will be clearly visible overshoot sparks.
Leakage current can be determined at the hearing. Evidence of the failure of the wires will be soft dry clicks.
In the end, you can measure the resistance of high-voltage wires, armed with a multimeter. The line of resistance wire, indicated in its isolation, with the result of the measurement can accurately determine the degree of serviceability of the conductor.
Be aware that a very common test "the spark", will not give you accurate and objective information about the state of the high-voltage ignition wires, since the candle will give out a spark even at break in the wire or in the case of failure of the suppression resistor. But its ability to produce a high quality electrical discharge within the combustion chamber during operation of the engine will be practically zero.
Good luck, and the ignition system of your car — good sparks!