How to Check the Low-tension Circuit in the Ignition System

How to Inspect the Ignition System in a Car?

A properly operating ignition system is vital for the effective functioning of a car’s engine. A fault in the ignition system can cause your car to become immobile. Since the ignition system primarily runs on electricity, using a multimeter, you can easily check each component of the system for any faults. However, there are other mechanical aspects that you also have to factor in while checking the system. Read on to find out how to inspect the ignition system in a car all by yourself.

Signs of a Faulty Ignition System

An ignition system can fail due to several reasons. Some of the signs to look out for are listed below.

The Car Fails to Start

If your car doesn’t start immediately or doesn’t start at all, there is likely a problem with your ignition system. Check for the correct amps by testing your car’s battery. Determine if the car needs a new battery or can be charged using a battery charger. Also, change the spark plugs if they appear damaged.

The Car Stops Working Randomly

If the car shuts down randomly and starts up again, this is a sign of a fault in ignition leads or a short circuit in the windings of the coil. Visually inspect the leads to spot any signs of damage. Also, replace any fuses that appear to be blown.

The Car Becomes Rough when Accelerated

If an increased acceleration causes your car to become rough, this might be a sign of water or oil seepage in either the coil, the ignition leads, or the spark plug connections. Check each component for any signs of oil or water inside them. Dry or replace them depending on the condition they are in.

The Car Starts Using too much Fuel

If your car is consuming more fuel than usual, it might indicate a problem with damaged or loosely fitted ignition leads. The leads have to be checked by a multimeter for any signs of damage.

Car’s Electrical Equipment Stops Working

The sudden failure of your car’s electrical equipment implies terminal burnout in the ignition system. Inspect all the terminals. Use a multimeter to detect voltage drop.

It can also be a sign of a fault in the voltage regulator. Check and fit a new voltage regulator if the old one is damaged.

Popping Noises from the Exhaust

If you hear strange popping noise from the car’s exhaust or the manifold, there is a problem with the ignition timing adjustment. The noise can also occur due to spark plugs with an incorrect heat rating. Make sure you only purchase the manufacturer-recommended spark plugs for your car.

How to Inspect the Ignition System

For a thorough inspection of the ignition system, follow the following steps:

Checking the Wiring and the Plugs

Step 1 – You have to start by visually inspecting all the wires and connections in the ignition system.

Wires are insulated with plastic, which is easily damaged due to high temperatures or kinks. Connections, on the other hand, can corrode due to moisture. You can either repair or replace the wires and connections depending on their condition.

Step 2 – Next, check the plug leads and connections for any loose fittings. Make sure the connections are tight, and the leads are kept dry. The lead should also not have any kinks or cracks in them so that they are less likely to be damaged.

Use guided clips to prevent them from coming in contact with hot surfaces and damaging their insulation. Replace them if they are damaged to increase the performance of the ignition system.

Step 3 – You have to make sure that the plug connections do not get mixed. You can mark them with sticky tape so that you know which connection goes where exactly in the distributor.

Step 4 – Using an emery cloth, you have to wipe the plug tops by removing the plug caps from the distributor. Clean plug tops ensure that there is no unwanted resistance in the electric current supply.

Checking the Distributor and Its Components

Step 1 – Remove the distributor cap and look out for any cracks. If you spot any signs of brittleness, it is best to get a new distributor cap.

Step 2 – You must ensure that the rotor arm can move freely. The spring contact on the top of the rotor arm should work properly and be free from any wear. You can clean and file the tip of the rotor arm if you notice any signs of pitting.

Step 3 – You now have to remove the rotor arm and inspect the contact-breaker points. Replace them if you notice excessive pitting on the points, that is, if there is a deposit of 1mm metal on one contact-breaker point.

Checking the Coil and Its Components

Step 1 – You then need to check the coil and the leads. Ensure the coil is attached to its mounting firmly and leads are accurately connected to the coil’s terminals. Incorrectly attached leads can cause misfiring in the system. 

Step 2 – A resistor is clamped to the coil in some cases. Ensure that the resistor is not damaged and works properly by testing it with a multimeter using the resistance feature.

Additional Test

For an additional test, park the car in a dark place and look for any electrical leakages from the ignition system in the form of blue sparks. The presence of blue sparks implies damaged or wet insulation. Dry or replace the component from where the leakage is occurring. But be careful while working on the car’s wiring system to avoid getting shocked or starting a fire accident.

And there you have it, a thoroughly inspected ignition system. Start the ignition and take your car for a drive.

Knowing how to inspect the ignition system of your car is a simple skill that can largely benefit you in keeping your car functioning. You do not have to wait for faulty signs to appear in an ignition system; regular inspection of the system ensures that your car operates at its optimum condition.

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