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Ignition Coil: Definition, Types, Working Principle, Construction & Problems Symptoms

Ignition Coil types and problems symptoms
What is Ignition Coil?
Ignition Coil types and problems symptoms :- An ignition coil which is commonly known as a spark coil is an induction coil used in an automobile ignition system that converts the cell voltage to a huge voltage. This voltage is required for the formation of an electric spark in a spark plug to burn the fuel. Some coils have an inbuilt internal resistor as other coils are having external resistance to limit current. The high voltage wires that cross through the ignition coil to the distributor and then through the distributor to each of the spark plugs are called spark plug wires.
Mechanical contact breaker points and a condenser are required in every ignition system. In today’s time, a power transistor is used by an electronic ignition system to provide pulses to the ignition coil. Diesel engine depends on compression to ignite the fuel/air mixture do not need an ignition system
Working Principle of Ignition Coil
Electronic ignition systems
Ignition Coil Construction
Ignition Coil types and problems symptoms :- In the earlier time, ignition coils were made with paper insulated high-voltage windings and varnish, fixed into steel can which is filled with oil for insulation and water protection. In modern automobiles, Coils are cast in filled epoxy resins which enter any air gap in the winding. Today’s single spark systems have one coil for one spark plug. To avoid early sparking at the beginning of the primary pulse, a secondary spark gap is placed in the coil to stop the reverse pulse.
Modern Ignition Systems
In modern systems, the distributor is not permitted and ignition is preferred to be controlled electronically. Small coils are being used with a single coil per spark plug. These coils may be mounted from anywhere or they can be installed on top of the spark plug which is known as Direct Ignition. Where one coil works for two spark plugs that are two cylinders. In this arrangement, the coil produces two sparks per cycle to both cylinders. The fuel in the cylinder that is almost finishes and compression stroke is ignited, whereas the spark in its partner that is almost the end of its exhaust stroke which does not affect.
The wasted spark system is more stable than a single coil system with a distributor and cheaper than a direct ignition. When the coils are individually applied per cylinder, they all are kept in a single mounded block with various high-tension terminals. This is called a coil pack. A bad coil pack will result in bad fuel consumption or loss of power.
Ignition Coil problems symptoms
There are bad ignition coil symptoms:
- Backfiring
- Fuel Economy
- Vehicle Stalling
- Engine Jerking, Rough idling, Poor Power
- The engine does not start
- The vehicle failed to start
- Poor acceleration or loss of power
- The engine control unit shifts to home mode
- Engine fault codes
- If the coil malfunction causes failure, then this will permit raw fuel to enter; permanently degrading the catalytic converter. To avoid engine damage we will take steps to check the oil leaks and spark plug issues
- The most common cause is an oil leak from the valve cover gasket. in many types engines, the spark plug and ignition coil are mounted under a spark plug tube. Around the division of the valve cover, This tube is fixed. after a years time, the seal between the valve cover & spark plug tube can break which cause oil leak and spread around the spark plug and ignition coil which is a reason for spark plug and ignition coil failure.
- Signs of disappointed ignition coils somewhere depend on the automobile system. If a vehicle having a single coil supporting the whole engine, then the engine will not work at all as the ignition coil collapses. This can appear suddenly. Vehicles having coil-on-plug ignition system, a bad ignition coil can create a misfire in one or more cylinders simultaneously. However, The engine will run but it will rough performance. Some coil-on-plug ignition coils command two cylinders by a waste spark system. In that type of system, some unusual mishappening takes place.
Types of Ignition Coil
Ignition coils are of four types;
- Conventional Ignition Coil
- Electronic Ignition Coil
- Distributor-less Ignition Coil (DIS)
- Coil-on-Plug Ignition Coil (COP)
1. Conventional Ignition Coil
The current flows through the distributor cap and finally into the spark plugs in few seconds. These earlier mechanical distributor systems had their weaknesses. The ignition points got to break down and change spark timing which decreases the engine efficiency. which cause to replacement
2. Electronic Ignition Coil: ( Types of Ignition Coil )
This ignition having most of the characteristics same as that of a conventional system. But in the place of a distributor cam and points, there is the electronic system that needs a pickup coil to signal the control module. Distributor shaft manages to develop a specific amount of “lash” after miles. So gear wear always be an obstacle to proper spark timing and the development of mechanical ignition systems is required.
3. Distributor-less Ignition Coil (DIS): ( Types of Ignition Coil )
In the distributor less ignition coil, its design permits more energy to be accessible through many coils. In a coil pack, there are three or more mounted collectively.
It uses a magnetic triggering device to find engine speed and crankshaft location. This system finds spark timing based on, two shaft location sensors and a computer. Crankshaft position sensors every time monitor both shafts’ locations and feed that information into a computer.
4. Coil-on-Plug Ignition Coil (COP): ( Types of Ignition Coil )
The coil-on-plug (COP) ignition system unites all the electronic controls that can be seen in a direct ignition system. But, in the place of two cylinders dealing a single-coil, each (COP) coil cooperates with only one cylinder. As a result, some (COP) ignition systems produce as much as 47,000 volts and much hotter sparks.
Finally, the Top Failure Reasons of coil on plug ignition coils:
Bad spark plugs
Bad plug wires
Voltage overload