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Car Ignition

Car keys in ignitionBy now you know that the engine needs air, fuel, and spark to start. So, how is the spark produced? As part of the ignition system, the ignition switch is the first step in getting your vehicle to start. The switch is at your very fingertips. That’s right, you have complete control! By the turn of a key or the push of a button, you’re sending a signal to the vehicle to begin the ignition process.

The Engine Ignition System

The ignition system consists of several components working together, controlled by the vehicle’s internal computer, to get your vehicle started. Beginning with the ignition coil, it takes power from the battery and turns it into a spark powerful enough to ignite fuel vapor. The coil itself is made up of two windings called the primary and secondary. The primary winding gathers the power to create a spark and the secondary’s job is to send it to the distributor. The distributor is a precise spinner that distributes the sparks via the spark plug wires to the individual spark plugs with precise timing by the use of a rotor. The spark plugs are plugged into the cylinder head. When the intake valves have distributed the proper amount of fuel and vapor into the cylinder, the spark plug produces a hot spark that ignites, creating combustion.

How a Car Ignition Switch Works

Located on the steering wheel on the column or dash area, the switch is the key to getting your car to start. The key is inserted to let you turn the switch from off to on, accessory, and start. Most vehicles today have keys that have a built-in chip that communicates with the vehicle’s computer. In fact, many vehicles today don’t use a key at all to turn the ignition switch. Instead, a button and a remote controller communicate with the car’s computer to let it know you are the correct person to start the vehicle. Once the communication is complete, the vehicle should start. Once you arrive at your destination, you reverse the action to turn the vehicle off.

Often the failure of the switch is caused when the mechanisms inside the switch wear out or break, the key wears out, or the chip in the key fob is faulty.

Ignition Coil

Past the switch, lies the ignition coil. How does a car ignition coil work? Located under the hood, this component also communicates with the computer to create the power to make the engine run. Once the ignition switch is prompted by key or the push of a button, it activates the voltage from the battery to the ignition coil to produce the engine spark. The engine spark from the coil or coils is directed to the spark plugs to ignite the fuel to make the vehicle run. Ignition coils take 12-battery voltage, and similar to a transformer, which boosts the power to about 30,000 volts.

Most common causes of failure of the engine voltage are the wiring to the coil, the coil windings, or the vehicle’s internal computer has failed. While moisture resistant, the coil cannot tolerate being submerged in engine water or oil due to leaks and may short out. Coils can drop in voltage as a result of a short or just normal wear. A faulty coil will often cause the engine to misfire. Since the coil voltage must be balanced between all of the engine cylinders, to allow a smooth engine operation, if any part of the equation is unbalanced, a misfire may occur.

Your Partner in Automotive Care

If your vehicle can’t create the spark, it simply won’t start. If you can’t get your car to start, getting to the shop for help can be a challenge and may necessitate the need for a tow truck. Luckily, Sun Devil Auto offers complimentary towing services with most major repairs. We’ll pick up your vehicle and deliver it to your favorite Sun Devil Auto location, inspect your vehicle to determine the cause of your car’s trouble, and repair it with your authorization. You’ll be pleased knowing that once your vehicle is repaired, the service is backed by a solid 2-year, 24,000-mile Nationwide warranty. That means you’ll be covered no matter where you are! When you’re in need of vehicle care from maintenance to repairs, we’re here to help. Just give us a call!