How many ignition coils are in a 4-cylinder engine?

Most modern 4-cylinder cars use four ignition coils—one per cylinder. However, depending on the ignition system design and vehicle age, a 4-cylinder engine can have one, two, or four coils. The exact number hinges on whether the engine uses a distributor-based system, a wasted-spark coil pack, or a coil-on-plug setup.

Why the number varies

Automakers have used different ignition architectures over time to balance cost, reliability, performance, and emissions. Older engines concentrated spark generation into fewer coils, while newer designs typically dedicate one coil to each cylinder for precise control.

Common ignition configurations in 4-cylinder engines

The following list explains the typical coil counts you’ll encounter in 4-cylinder passenger vehicles, along with how each system works and where it’s most commonly found.

• 1 coil (Distributor ignition): A single coil feeds a distributor, which mechanically routes high voltage to all four spark plugs. Common in older vehicles (pre-1990s to early 1990s).
• 2 coils (Wasted-spark coil pack): Two coils each fire a pair of cylinders simultaneously (one on the power stroke, one “wasted” on the exhaust stroke). Widely used from the mid-1990s through early 2000s on many models.
• 4 coils (Coil-on-plug or coil-near-plug): One coil per cylinder, mounted directly on the spark plug (or very close). Standard on most modern vehicles from the 2000s onward for better control and diagnostics.
• Integrated coil packs: Some 4-cylinder engines use a module that looks like a single “pack” but contains two internal coils (wasted-spark) or four individually controlled coils (less common). Count the towers or check specifications to know what’s inside.

In practical terms, if your 4-cylinder car is from the last 15–20 years, it most likely has four coils. Earlier models may have two (wasted-spark) or one (distributor), depending on the year and manufacturer.

How to confirm what your vehicle has

If you’re unsure about your specific engine, these steps will help you identify the ignition setup and coil count without guesswork.

1. Look under the ignition cover or engine cover: Coil-on-plug systems have a small coil atop each spark plug—typically four identical units along the valve cover.
2. Check for a coil pack with multiple towers: A 4-cylinder wasted-spark pack usually has four plug-wire towers but contains two coils inside.
3. Check for a distributor: A round cap with multiple plug wires indicates a single-coil distributor setup.
4. Consult the owner’s manual or service manual: The ignition system type and parts diagrams will specify coil count.
5. Use a parts catalog by VIN: Dealer parts sites or reputable aftermarket catalogs list the exact coil type and quantity for your VIN.

These checks will quickly reveal whether your engine uses one, two, or four coils and help you order the correct parts or plan repairs.

Why modern engines use one coil per cylinder

Manufacturers shifted to coil-on-plug systems for several technical and regulatory reasons that improve how engines run and how easily they can be serviced.

• Stronger, more precise spark: Individual coils allow optimized timing and dwell for each cylinder, improving efficiency and power.
• Lower emissions and better fuel economy: Precise ignition control helps meet stricter emissions standards.
• Improved reliability: Eliminates high-voltage plug wires and moving parts like distributors, reducing misfire risks.
• Simpler diagnostics: On-board systems can flag a specific misfiring cylinder (e.g., P0302) and its coil for targeted repair.

Collectively, these advantages made coil-on-plug the dominant architecture for modern 4-cylinder engines, explaining why four coils are now the norm.

Maintenance, symptoms, and costs

Failing coils can cause rough idle, misfires under load, loss of power, poor fuel economy, hard starts, and an illuminated check engine light. On coil-on-plug systems, replacements are typically done per affected cylinder unless age or mileage suggests doing all four. Parts costs commonly range from about $30–$150 per coil (aftermarket versus OEM), plus labor; wasted-spark coil packs often cost $80–$300 for the assembly. Actual pricing varies by make, model, and region.

Summary

A 4-cylinder engine can have 1, 2, or 4 ignition coils, depending on the ignition system design. Most modern vehicles use four coils (one per cylinder), while older cars may use two coils in a wasted-spark setup or a single coil with a distributor. Visual inspection, manuals, or VIN-based parts lookups will tell you exactly what your vehicle has.

Should you replace all four coils at once?

No, you don’t always have to replace all four ignition coils at once; it’s often best to replace only the failed one, but replacing all of them can be a cost-effective long-term strategy if the vehicle is older, the coils are inexpensive, or they are difficult to access for future replacement. If you replace only one, be prepared for the possibility that other old coils may fail soon after. 
When to replace only the bad coil

• Cost-effective: Opens in new tabReplacing only the one that failed is the most budget-friendly option in the short term. 
• Still functioning: Opens in new tabYou can replace just one if the other coils are relatively new or still in good condition. 
• Vehicle age: Opens in new tabIf the vehicle is newer and the coils are not old, it’s less likely that others will fail soon. 

When to replace all coils

• Older vehicle: If your vehicle has many miles on it, replacing all the coils at once ensures optimal performance and prevents future issues. 
• Coils are inexpensive: If the coils are not costly, the combined price for all of them might make it worthwhile to replace the set. 
• Hard-to-reach coils: If coils are in a hard-to-access location, replacing them all at once is a practical approach to avoid repeated labor costs. 
• Prevent future hassle: You can avoid the inconvenience and potential downtime from repeated individual coil failures by replacing the whole set at once. 

Considerations

• Engine performance: Opens in new tabReplacing all coils can ensure smoother engine operation and better performance, as it avoids mixing new and old coils. 
• Spark plugs: Opens in new tabIt’s often recommended to change the spark plugs at the same time, as new spark plugs help the new coils do their job effectively. 

What are the symptoms of a failing ignition coil?

Symptoms of a failing ignition coil include a Check Engine Light, engine misfires and rough idling, stalling, loss of power, poor fuel economy, difficulty starting the engine, and exhaust backfiring or a smell of gas. These issues occur because the coil fails to deliver enough voltage to the spark plugs, preventing proper combustion. 
Common Symptoms

• Check Engine Light: A blinking or steady Check Engine light often indicates a misfire, which is a common sign of a failing ignition coil. 
• Engine Misfires/Rough Idling: You may notice a jerky or stuttering motion while driving, or the engine may feel unstable and vibrate when idling. 
• Stalling: The engine might cut off or stall when you come to a stop. 
• Loss of Power: The vehicle may feel sluggish, especially during acceleration, due to incomplete combustion in the cylinders. 
• Poor Fuel Economy: With less efficient combustion, your car will consume more fuel, leading to lower gas mileage. 
• Difficulty Starting: The engine may crank longer or fail to start altogether. 
• Exhaust Backfiring: You might hear a sputtering or coughing sound from the engine or tailpipe. 
• Smell of Gas: An incomplete combustion process can send unignited fuel into the exhaust, creating a gas smell. 

What’s Happening Inside the Engine
A failing ignition coil cannot provide the proper voltage to the spark plug. This leads to: 

• Incomplete Combustion: The fuel-air mixture in the cylinder doesn’t ignite correctly. 
• Misfires: The spark plug fails to do its job, causing the engine to misfire. 
• Engine Performance Issues: The misfires disrupt the smooth operation of the engine, resulting in the symptoms listed above. 

Is the ignition coil d cylinder 4?

Yes, “Ignition Coil D” typically refers to the ignition coil for Cylinder 4 in most vehicles, and a diagnostic trouble code (DTC) like P0354 indicates a malfunction in that specific coil’s circuit. The vehicle’s computer monitors the coil’s performance, and if it detects issues with the primary or secondary circuits, it triggers this code and illuminates the check engine light.
 
This video explains how to diagnose a P0354 code and check the ignition coil: 1mWeeklyToolsYouTube · Mar 13, 2024
What “Ignition Coil D” Means

• DTC P0354: Opens in new tabThis is a common diagnostic code meaning “Ignition Coil D Primary/Secondary Circuit Malfunction”. 
• Cylinder Designation: Opens in new tabIn most engines, the letter “D” in “Ignition Coil D” is a label for the ignition coil associated with cylinder number 4. 

Common Causes and Solutions

• Faulty Ignition Coil: The most common cause is a failing ignition coil itself. 
• Wiring or Circuit Issues: Problems with the wiring harness or connectors, such as damage, corrosion, or loose connections, can cause this code. 
• Bad Spark Plug: In some cases, a faulty spark plug can contribute to the ignition coil circuit malfunction. 
• Solution: To resolve this, you typically need to:
  1. Inspect: the ignition coil, wiring, and connectors for damage. 
  2. Test: the coil’s resistance using a multimeter. 
  3. Replace: the faulty ignition coil if it’s defective or repair any damaged wiring. 
  4. Ensure: the spark plug is in good condition. 

You can watch this video to learn how to fix the P0354 code by swapping the coil: 36sTheEtixzShowYouTube · Apr 3, 2022

How many ignition coils do I have?

Your car’s computer controls when each coil fires, based on input from various sensors. Typically, you’ll have one ignition coil per engine cylinder—so four coils in a four-cylinder engine, six in a six-cylinder, and so on.