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How to Buy Performance Spark Plugs and Ignition Coils

How to · Auto

How to Buy Performance Spark Plugs and Ignition Coils

Upgrade your ignition system during holiday sales and pay it off over time without interest.

VoAtlas editorial Updated · 3 min read
Typical cost $350 before anything else
Across the 0% window $19.44/mo 18 months, no interest

How we got that: $350 spread evenly across the 18-month introductory window on the Citi Simplicity® Credit Card. Checked · at the bank Carry a balance past the window and the standard APR applies to what is left.

Keeping an older engine running smooth means staying ahead of worn parts, and a weak ignition system robs you of power and fuel economy. Performance spark plugs and ignition coils usually run about $350, and the best time to buy them is during the big holiday parts sales when online retailers drop prices. You want fresh components when misfires start creeping in, not after they leave you stranded.

We can time this purchase for the discounts, but let's talk about how to handle the payment. A financing window gives you breathing room, but you still need a clear plan to cover the total cost before the clock runs out.

Remember that this 0% window is a hard deadline, not free money. If you still have a balance left when those 18 months are up, interest will hit the remaining amount hard.

The steps

  1. 01

    Hunt for holiday sales

    Wait for major holiday weekends when performance auto parts websites run storewide discounts. Put the parts in your cart beforehand so you notice the exact moment the price drops.

  2. 02

    Check part numbers twice

    Aftermarket ignition parts can look identical while having different heat ranges or electrical resistance. Cross-reference the manufacturer part numbers with your specific engine code before you check out.

  3. 03

    Set up your payment window

    You can use the Citi Simplicity® Credit Card to get 0% for 18 months on purchases and balance transfers from date of account opening. This gives you plenty of time to clear the balance without paying extra in interest.

  4. 04

    Automate your monthly math

    Divide your total by the months you have left. If you spend $350, it breaks down to about $19.44 per month to wipe it out completely before the promotion ends.

  5. 05

    Keep the garage clean

    Block off a couple of hours for the install so you are not rushing through torque specs or gap measurements. Keep your receipts organized in case any of the new coils fail under warranty.

  6. 06

    Check the card terms before you commit

    Every figure we publish for the Citi Simplicity® Credit Card carries the date a person verified it against Citi and a link to where they checked. Intro windows and APRs change without notice, so confirm the current terms before applying.

    See Citi Simplicity® Credit Card terms →

Common questions

How often do spark plugs and ignition coils need replacing?

Standard copper plugs usually need swapping every 30,000 miles, while iridium options can last up to 100,000 miles. Ignition coils generally get replaced only when they start causing misfires, but doing them alongside high-mileage plugs saves you time.

Should I replace the coils if only one is bad?

It is usually smart to replace the whole set if your car has high mileage and they are all the same age. If one has failed, the others are likely not far behind.

Do I need to gap performance spark plugs?

Many modern performance plugs come pre-gapped, but you should always check them with a tool before installation. Dropping a plug in the box can easily close the gap.

What happens if I miss a monthly payment during the 0% window?

Missing a payment can trigger late fees and might cancel your promotional rate early. Set up automatic minimum payments just to be safe, even if you plan to pay more.