{"id":8251,"date":"2020-08-26T01:01:31","date_gmt":"2020-08-26T08:01:31","guid":{"rendered":"https:\/\/carupgrade.co\/?p=8251"},"modified":"2020-11-12T05:50:17","modified_gmt":"2020-11-12T13:50:17","slug":"bad-ignition-coil-symptoms","status":"publish","type":"post","link":"https:\/\/carupgrade.co\/blog\/bad-ignition-coil-symptoms\/","title":{"rendered":"Signs Of A Bad Or Failing Ignition Coil"},"content":{"rendered":"\n

A bad ignition coil can give you trouble while starting your car. An ignition coil transforms the energy in the battery to a higher voltage to ignite the fuel in the cylinder. If your vehicle loses power as you drive on the highway, here is what could happen and what could be causing it. However, first, let\u2019s get through how it works in order to understand how such signs are produced.<\/p>\n\n\n\n

How Does The Ignition Coil Work?<\/h2>\n\n\n\n

An ignition coil is a mini electrical transformer fitted in your car, converting the normal 12-volt current found in the car battery to ignite the fuel and start the engine. Ignition coil has its own spark plug connected to it by a wire or sitting on its top. It needs 15,000 to 20,000 volts of electricity for a spark plug to generate a spark to ignite the fuel. The coils are usually protected in oil-filled housing, which acts as a refrigerant. It has two windings wrapped around the iron core; primary and secondary. This arrangement makes the ignition coil a compact step-up transformer. The number of turns of the secondary winding is always more than the primary winding resulting in a higher conversion of current.<\/p>\n\n\n\n

If the ignition coil is unable to transform the energy strongly, then the fuel consumption is weaker, which results in the engine misfiring. The older car batteries can easily breakdown with time; it should at least read 12.65 volts in a fully charged state, or otherwise, this is a sign of a bad ignition coil.<\/p>\n\n\n\n

7 Bad Ignition Coil Symptoms<\/h2>\n\n\n\n

Experiencing driving issues related to combustion process hints possibly towards a bad ignition coil. We have compiled a list of common symptoms to understand when your ignition coil has gone bad. Note that each symptom would differ depending on the severity of the breakdown.<\/p>\n\n\n\n

1. Backfiring<\/h3>\n\n\n\n

Backfiring is one of the most common signs of a bad ignition coil. Backfiring refers to the condition when the unused fuel left in internal combustion cylinders ends up flowing out of the exhaust pipe. The ignition coil malfunctions and doesn\u2019t spend enough signals to the spark plugs leaving unused fuel behind. This makes the fuel-to-air mixture too rich, and the unused fuel starts coming out of the exhaust. Ignoring this sign is a bad idea because it can result in costly repairs lately. <\/p>\n\n\n\n

The usual sign of backfiring is the black smoke coming out of the exhaust pipe. The smoke may also give off gasoline smell indicating the ignition coil failure. The smell comes off the unused fuel exploding before coming out, resulting in greater damage to the engine later on.<\/p>\n\n\n\n

2. Engine Misfiring<\/h3>\n\n\n\n

If you turn on the car engine and hear a coughing or spluttering sound, again and again, it indicates that the engine is misfiring or doesn\u2019t fire at all. Engine misfiring usually results from a bad ignition coil. Your car will start jerking and spitting at high speed. It will vibrate upon idling at a signal. Misfiring usually happens when the engine is under load. Your car will even hesitate while accelerating, and you would feel like you are missing on the power to drive. The dense emissions can ruin other important parts like catalytic convertor or air-fuel mixture sensors. This can result from a fuel delivery system or spark plug problems too. You can still drive your car, but it\u2019s better to take it to the mechanic as soon as possible.<\/p>\n\n\n\n

3. Stalling Vehicle<\/h3>\n\n\n\n

A failing ignition coil will cause vehicle stalling. Your car will come to a stop completely while idling, leaving you confused as you try to restart it repeatedly. The faulty ignition coil sends the inadequate spark to the spark plug resulting in installing a vehicle. If the problem is ignored and aggravated, your car will stop suddenly while starting, accelerating, stopping, or simply driving. Transmission problems, idle air control actuator or a clogged EGR valve could also result in such conditions. You need to get it checked at an auto shop near you.<\/p>\n\n\n\n

4. The Engine Is Hard To Start<\/h3>\n\n\n\n

A hard starting engine is a sign of a car with one ignition coil. If the vehicle totally depends on a single ignition coil, its malfunction will cause you a lot of trouble even though problems can result in more than one coil installed. This issue has no relation with configuration. If the spark plug doesn\u2019t receive much power, you will not be able to start your car. The cranking sound of the cylinders indicates the weak sparks but a working ignition coil. The cranking sound of the cylinders indicates the weak sparks but a working ignition coil.<\/p>\n\n\n\n

5. Leaking Oil<\/h3>\n\n\n\n

A malfunctioning ignition coil can overheat in no time. This results in the housing wiring to break leaking the oil into the surroundings. The leaking oil could also result from a gap in spark plugs due to corrosion. The ignition coil works at a higher voltage, and as it is already working harder, it will overheat.   <\/p>\n\n\n\n

6. Check The Engine Light<\/h3>\n\n\n\n

If you find the engine\u2019s light on at your dashboard, unexpectedly, this means that there is something up with the ignition coil. You can drive your car to the mechanic for the OBD-II check. The engine will show up with the DTC code P0351 upon the check, which predicts ignition coil, primary, or secondary circuit malfunction. You can grab an OBD scanner and check it on your own to troubleshoot a coil issue.<\/p>\n\n\n\n

7. Poor Fuel Economy<\/h3>\n\n\n\n

Another evident symptom of a bad ignition coil is poor fuel economy. You can easily determine your car\u2019s average fuel consumption if you have been driving it for a while. If these days your car is offering less mileage with the same amount of fuel, then you need to check on the ignition coil. The system compensates the lower power generated by the spark plug by utilizing more fuel. This also happens due to the malfunctioning of oxygen sensors. A bad fuel injector can also leak the fuel.<\/p>\n\n\n\n

How To Prevent A Bad Or Failing Ignition Coil<\/h2>\n\n\n\n

The best way to keep your car in good shape is to pay close attention to every part of the ignition system. Keeping an eye on the spark plug can help you to save money in the long run, saving you from costly repairs. Check the plugs for erosion and if they aren\u2019t worn out. Check for the housing for leakage. Check for the ignition system wires not to be toasted, and in case you find any of the above-listed things in bad shape, then go for maintenance as recommended by your vehicle manufacturer.<\/p>\n\n\n\n

Testing A Failing Ignition Coil<\/h2>\n\n\n\n

Based on if the coil is CNP (Coil-Near-Plug) or COP (Coil-On-Plug), here is how you can test an ignition coil.<\/p>\n\n\n\n

COP Coil Type:<\/h3>\n\n\n\n