How Long Do Coil Packs Last?

Reviewed by

Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Written by CarParts.com Research Team - Updated on October 3rd, 2024

Reading Time: 5 minutes
Summary
  • Manufacturers typically design ignition coils to last the vehicle’s lifetime, so you don’t need to change them as often as your tires or motor oil. However, ignition coils can fail due to poor maintenance, incorrect air-fuel ratio, valve cover leaks, and other factors.
  • Ignition coils can last anywhere between 120,000 to 150,000 miles or five to seven years, but this can still change depending on several factors, such as your driving habits and your vehicle’s year, make, and model.
  • When an ignition coil fails, there’s a big chance that the other coils aren’t too far behind either, so it’s best to replace the entire coil pack if you don’t mind spending more.

Most modern vehicles are equipped with a coil pack, an electronically controlled pack of ignition coils that transform the battery’s low voltage into thousands of volts needed by the spark plugs to trigger ignition. As one of the most important parts of your engine, coil packs can make or break the entire combustion process.

Most vehicles with coil packs (not the same as “coil on plug” coils) will have the same coil packs on them when they’re retired from the road as they had when they came out of the factory, but coil packs do fail in various ways.

Comparison between COP coils and a coil pack | Image Source: Richard McCuistian

Should You Replace Coil Packs Regularly?

Ask around and you’ll likely get different answers. Some believe ignition coils should be replaced regularly, while others think it isn’t necessary. Manufacturers typically design ignition coils to last the vehicle’s lifetime, so you don’t need to change them as often as your tires or motor oil. However, ignition coils can fail due to increased resistance in aging ignition components. As plugs wear, they require more voltage to fire.

A vehicle that has multi-strike idle spark and spends too much time idling that it will wear the coil out faster than a vehicle that is driven on the highway because the coil will fire two to four times during every firing event when the vehicle is idling.

As the spark plugs wear, the coil pack has to work harder to fire the plug, and since the high voltage spark is always looking for the easiest path, sometimes the coil pack will fail due to excessively worn plugs or internally compromised spark plug wires.

The scope pattern on the left was captured before the spark plug was replaced and the pattern on the right is the same cylinder with a new spark plug. Notice the much greater stress in the firing pattern with the old spark plug than with the new. The coil pack was having to work a lot harder due to the worn-out spark plug, which is much harder to fire than a new spark plug. Notice that the coil fires the plug on this 2006 Explorer at idle. | Image Source: Richard McCuistian

The alternator’s target voltage is usually between 14 and 14.5 volts.

Richard McCuistian, ASE Certified Master Automobile Technician

How Long Do Coil Packs Usually Last?

It’ll depend on several factors, including your vehicle’s year, make, and model. In general, however, ignition coils can last anywhere between 120,000 to 150,000 miles or five to seven years. It’s a good idea to check on them before then, so your mechanic can identify any issues before they negatively affect your vehicle.

Factors That Affect the Lifespan of Coil Packs

While ignition coils are typically made to last, there are several factors that can affect their lifespan. Here are some examples:

Vehicle Year, Make, and Model

Some vehicles come with ignition coils that last longer than others. Because of this, it’s always a good idea to research the common issues of your car’s specific year, make, and model to see if other owners have also experienced issues with their vehicle’s ignition coils. Note, however, that even on the same vehicle make, some coil packs are more robust than others, depending on the design.

Vehicle Age and Mileage

The longer you’ve been driving your car, the more issues pop up. This is because most parts of your vehicle naturally wear over time, including the ignition coils. The constant demand on your vehicle’s ignition coils can cause them to show signs of wear or even fail.

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: The problem is that unless there are visible sparks popping where the coil has failed, you can’t detect a bad coil with the naked eye. But replacing the spark plugs according to OEM recommendations will go a long way toward extending the life of the coil pack.

Driving Habits

Accelerating right after stopping your vehicle and pushing it to its maximum speed can negatively affect the lifespan of your ignition coils. Driving habits like these force your ignition coils to work harder, causing them to wear faster.

Regular Maintenance

Never underestimate the importance of keeping up with your vehicle’s maintenance schedule. Different manufacturers will recommend different service intervals, so be sure to double-check when you’ll have to service your spark plugs.

Quality of Ignition Coils

You want to get a high-quality ignition coil pack if you want it to last. High-quality ignition coils might be pricier, but they’re worth the money. You might have to shell out more money initially, but because you won’t have to replace it again, you’ll save more money in the long run.

Should I Replace All Ignition Coils At Once?

Some engine platforms (Like Crown Victoria 4.6L engines pre-1998) will have two separate coil packs. When one coil pack goes bad, do you really have to replace both of them? If you’re on a budget, then you can just replace the faulty one, but if you don’t mind spending more money, we suggest replacing them both, or if you’re working on a coil-on-plug engine, all of them.

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How To Tell if a Coil Pack Is Bad

It can be hard to diagnose a faulty coil pack, mostly because the symptoms can be similar to a faulty spark plug. However, if you suspect your coil pack is damaged, here are some signs to look out for:

  • Rough Idle
  • Misfires under load or at 45-50 mph steady cruise.
  • Visible spark leak at the coil.
  • Blinking check engine light.

Can You Drive With a Faulty COP Coils?

While coil-on-plug (COP) engines can still run with failed coils, it’s not a risk you should take. Faulty COP coils can damage your engine and crankshaft, leading to costly repairs down the line. In some cases, damaged ignition COP coils can also prevent your car from starting. For your own sake, it’s best to avoid driving until you replace the parts.

How Much Does a Coil Pack Cost?

The final price of a coil pack replacement will vary depending on several factors, including your vehicle’s year, make, and model. In general, however, you can expect to spend anywhere from $10 to $1360 for a new ignition coil.

Reviewed By Richard McCuistian, ASE Certified Master Automobile Technician

Technical Reviewer at CarParts.com

Richard McCuistian has worked for nearly 50 years in the automotive field as a professional technician, an instructor, and a freelance automotive writer for Motor Age, ACtion magazine, Power Stroke Registry, and others. Richard is ASE certified for more than 30 years in 10 categories, including L1 Advanced Engine Performance and Light Vehicle Diesel.

Written By CarParts.com Research Team

Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

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CarParts.com Research Team and Richard McCuistian, ASE Certified Master Automobile Technician