The Basics of Car Maintenance: How To Tell If a Spark Plug Is Bad

September 2, 2020Car Care and Revamp
Eva Johnson

Digital nomad born in New York but currently living online, Eva knows everything there is to know about packing and moving.

If you’re planning to relocate cross country soon, booking car shipping is probably one of the most important tasks on your moving checklist. That’s why a vehicle inspection is a must in order to get a picture of its overall condition. How to tell if a spark plug is bad is one of the common questions that car owners deal with and can be answered through a routine check.

Moving to another state or overseas and bringing your vehicle often means you’ll need to consider getting professional services to ship your car cross country. This process is quite straightforward but requires patience, dealing with a lot of paperwork, and above all, transporting an operable and functional car to your new home.

When starting from scratch, it’s always a good idea to organize and declutter all your belongings, toss old and broken ones, or repair those you still use and love. The same goes for your car. Bringing it to the new place in excellent condition will release you from additional worries and expenses. Adjusting to a new environment is a stressful process that people generally don’t like, so why complicate it further?

These are essential maintenance items you shouldn’t neglect or overlook as a car owner. One of the reasons for that is because their replacement doesn’t require too much work. Still, they play an important role in engine performance and can cause a host of problems if they’re faulty.

Let’s find out what these devices are, how they work, what types exist, and how to identify symptoms of bad plugs. These will help you spot a potential problem more easily before your trip and give the answer to the question How do you know when to replace a spark plug?, before you relocate.

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What Is a Spark Plug

This is a part of an engine that produces a spark that makes the fuel burn. Simply put, they keep your motor running strong and smooth. They are designed to transmit an electrical signal from the ignition coil to make a spark. This further ignites the air-fuel combination inside the combustion chamber.

Each car requires a particular type of these devices made from specific materials and a gap set by a mechanic during installation. It’s recommended to service them every 30,000 to 50,000 miles, depending on your car model. Some newer vehicles, SUVs, and trucks boast advanced combustion systems that seemingly make this replacement unnecessary. Still, if specific symptoms occur, they shouldn’t be ignored since they are relevant indicators that something is wrong.

Learn More About the Various Types

People usually think that all plugs are the same. But, those who are a bit more familiar with the ignition system, performance, and efficiency, know there are several types of these devices. You should choose those products your car manufacturer recommends. Let’s take a look into details and find out what they are suitable for:

  • Those made from solid copper have a central electrode made of nickel alloy, which is soft and not very durable, so it won’t last long. They are best to use in older vehicles without high electrical needs. If you need this component at affordable prices but still of high quality, you can find it at the Champion
  • Iridium ones are more expensive but will last the longest. Their center electrode is small, meaning they use less voltage to produce an electric current. The most famous brand manufacturers are NGK and Denso.
  • Platinum components are similar to those made of copper, but there’s one difference. Their center electrode has a platinum disc connected to its tip area. That being said, the platinum devices are more durable – they can last as many as 100,000 miles. Another advantage is the reduction of debris buildup thanks to the possibility to generate more heat. These are recommended for new cars with an electronic distributor ignition system. Manufactured by Bosch, they are designed to deliver the most potent spark to increase engine output.
  • Double platinum plugs are recommended for waste spark systems, which causes the component to fire twice. First in the compression stroke’s cylinder, and the second time in the exhaust stroke’s cylinder. These systems are not affected by rain or dampness. Arguably the best brand of double platinum plugs is Bosch.
spark plug
If you like Bosch products, you can opt for some of the best devices depending on your car model

How to Tell if a Spark Plug Is Bad

Luckily, these components don’t require replacement very often, and they can go many miles for years before the time comes to change them. Their durability depends on their condition and type, your vehicle, and your driving habits. As time goes by, the device ages and undergoes wear and tear despite the most robust material it’s made of. In addition to visual inspection, which should be performed occasionally, there are also signs of worn plugs. You can hear or feel them, You will notice your vehicle having trouble starting, poor performances, or constant and unusual noises, like pinging or rattling. So, let’s learn more about these symptoms in order to prevent further problems.

spark plug
Hear and feel your car to find out whether it's high time for maintenance

Failing Ignition System – Find Out the Symptoms

Appropriate and prompt maintenance improves your car’s longevity, creating a better driving experience at the same time. In case you forget to take your car in for a regular checkup, it can start showing symptoms that inform you it’s time to replace the component. These are:

  • The car is hard to start
  • The motor misfires
  • The vehicle gets poor fuel economy
  • Rough engine idle
  • The car has difficulties accelerating
  • The engine produces a loud noise
  • The check motor light is on

An Ignition Problems Test With a Bluetooth Scanner Will Enable Accurate Car Diagnostic

Suppose you cannot visit your mechanic and your car is exhibiting some of the mentioned symptoms. In that case, the best solution is a Bluetooth scanner that tests your combustion system, providing you with a complete diagnosis. How does it work? It’s simple to use, and you can easily test ignition circuit continuity at each cylinder following these steps:

  • With the engine off, remove all relevant the wiring
  • Attach the black connector
  • Put the metal end of the tester into the wire
  • Try to start your motor
  • When the ignition circuit is complete, you’ll notice a bulb flashing

Changes in the Device Itself That Indicate Breakdown

Another useful DIY diagnostic method is determining the condition of your engine by looking at your plugs. If you’ve already done this, you know how to differentiate between bad and good devices. But don’t worry if you’re not familiar with this process. We’ll help you find out if there’s some more life left in yours thanks to these six stages of wear and tear:

  • Normal wear – if the center electrode has worn away, that’s normal. This means that your motor is in excellent condition, but you should consider changing your plugs.
  • Black and dry – if this happens only on one cylinder, the problem is a leaky fuel injector. But, in case your cylinders are covered in this black stuff, your automobile probably dealing with the overall fuel control problem.
  • Clean plug – a spotless device usually means that your vehicle’s coolant steam cleans the tip of the device with its steam
  • Slight discoloration – if the color is slightly different, the electrode has worn out evenly, and there are no visible deposits, which means a normal condition, and you don’t need to do anything
  • Sandy electrode – with a dry and sandy look of the component, your car is probably facing a bad valve seals problem, meaning the oil is leaking into the motor and soaking valve seals or gates
  • Greasy plug – this is the worst possible scenario because it means there is an oil leak from the engine bottom going around the piston. If this happens, your motor will definitely need some major repairs.

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How Often Should You Change the Device

If you have your car owner’s manual, you’ll find the answer to this question there – a replacement is usually required every 30,000 miles. You can expect increased engine problems by neglecting this fact, such as uneven idling, misfiring, or lack of proper acceleration. Replacing the device on a four-cylinder engine is usually a straightforward task, and you should be able to handle the whole project yourself. However, some motor models require professional help, so contact your mechanic.

Changing Takes Longer With a V6 or V8

With V6 or V8 engines, replacing plugs gets more complicated. These motors may be more challenging due to the working space, which is tighter and crammed with too many electronics. That’s why you should let your mechanic get this done.

Honda CR-V Odyssey Needs Replacing Every Seven Years, but What if the Spark Plug Hasn’t Been Changed for a Long Time?

Plugs in Honda CR-V Odyssey are among the best ones. They are made from platinum and require replacement every seven years or 105,000 miles. But, what will happen if you forget or just leave these components in your car longer than recommended?

It’s good to know that even replacing at 100,000 miles can be troublesome because of carbon and corrosion that have accumulated there over the years. Then, there’s the possibility of damaging the threads in aluminum cylinder heads. So, don’t wait for the last minute to replace the component, regardless of its long life (iridium- or platinum-tipped). If there is a problem, it can be replaced earlier, and that’s how you’ll preserve the vital functions of the whole machine.

Long-life devices should be replaced at 100,000 miles, but if problems occur, you should change them earlier

What Are the Benefits of Getting a New Plug?

In addition to starting your car without a hitch, new plugs will lead to:

  • Consistent production of the optimal combustion system
  • Your fuel economy can increase up to 30%
  • Dealing with jerky starts is a past – your car will get smooth and energetic starts
  • Regular replacements save gas but also reduce air pollution
You don't need to make this a yearly habit, but do change this component regularly

With Your Vehicle’s New Plugs and Perfect Engine, You’re Ready for Auto Transport

We hope you realized that a plug is an essential part of your automobile, and its regular inspections and changes are among vital preconditions for your engine’s good health. If you’re planning to move a vehicle to another state or overseas, there’s nothing to fear about. With reliable shippers, you will define all the details, including auto transport service and necessary documentation. Furthermore, after auto services and car mechanic checkouts, you can rest assured that your vehicle will reach your new destination in perfect condition, no matter whether you opt for an open trailer or enclosed auto transport. Still, depending on the model of your car and weather conditions, you should consider the most convenient way of transporting the vehicle. Keep in mind that looking after your vehicle’s exterior is as important as routine maintenance, so make sure to prepare a car for shipping in time.

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