Where Ignition Coils Are Located

Ignition coils are typically mounted directly on top of each spark plug on the engine’s cylinder head (coil-on-plug), or grouped together in a coil pack on or near the engine—often on the valve cover, intake manifold, timing cover, firewall, or a fender; older vehicles may have a single coil on the firewall or intake area, while diesel engines don’t use ignition coils at all. The exact location depends on engine design, model year, and manufacturer packaging.

Why Ignition Coils Matter—and What “Location” Really Means

Ignition coils convert battery voltage into the high voltage that fires spark plugs. Where they sit is dictated by how the spark is delivered: either individually at each plug, in packs feeding multiple plugs, or as a single coil feeding a distributor. Modern designs prioritize short high-voltage paths and compact packaging, which is why many late-model engines hide coils under decorative engine covers.

Common Locations by Ignition Setup

The following list outlines the most common coil locations you’ll find across modern and older vehicles, grouped by ignition system type. Use it to match what you see under the hood with the most likely placement.

• Coil-on-plug (COP): One coil per cylinder mounted directly over each spark plug on the cylinder head, usually beneath a plastic engine cover. Common on most 2000s–present cars (Toyota, Honda, BMW, VW/Audi, Ford, etc.).
• Coil-near-plug (CNP): One small coil per cylinder mounted on or near the valve cover with short plug wires to the spark plugs (e.g., many GM LS-series V8s).
• Wasted-spark coil pack: A multi-tower coil pack mounted on the valve cover, timing cover, firewall, or a bracket on the engine, feeding pairs of plugs via traditional wires (seen on many 1990s–2000s engines).
• Single coil with distributor (older vehicles): A single cylindrical or square coil mounted on the firewall, fender, or intake manifold area, with a thick high-tension lead to a distributor.
• Motorcycles/small engines: Often coil-on-plug or a small coil module near the cylinder head or frame rail with a short lead to the plug.

If your vehicle aligns with one of these setups, you can narrow the search quickly: look for identical modules on the head (COP), small coils along valve covers (CNP), or a multi-tower pack or single canister on a bracket or firewall (wasted-spark/single-coil systems).

Quick Steps to Physically Find the Coils

Use these steps to locate ignition coils safely and efficiently, especially if engine covers or tight packaging obscure your view.

1. Open the hood and identify the cylinder head(s): Inline engines have one valve cover; V engines have two; boxer engines have heads on each side.
2. Remove any plastic engine cover: Look for small bolts or clips; most covers lift off after removing a few fasteners.
3. Trace the spark plug path: Follow either coil packs and short boots (COP/CNP) or plug wires from the head to a coil pack or single coil.
4. Look for telltale connectors: Coils have a two- to four-pin electrical connector and are often held by one or two small bolts (commonly 8–10 mm).
5. Check common mounting points: Valve covers, the top/front of the engine (timing cover area), firewall, or inner fender/bracket near the engine.

Once you’ve identified the ignition route—directly atop the plugs, along the valve cover, or via plug wires to a pack—pinpointing the coils becomes straightforward.

What They Look Like: Visual Cues

Coil-on-plug units resemble small rectangular or pencil-like modules with a rubber boot that slips into the spark plug well. Coil-near-plug modules are compact coils bolted along the valve cover with very short leads. Wasted-spark packs feature multiple high-voltage towers for traditional plug wires. Older single coils are cylindrical “can” or block-shaped units with one high-tension output and two small primary terminals.

Layout by Engine Type

Inline (I4, I5, I6)

Expect a straight row of coils atop the single valve cover, often under a long plastic cover. Each coil plugs directly into a spark plug well.

V Engines (V6, V8, V10)

Coils are split across two banks. COP systems place one coil per cylinder on each bank; CNP systems often mount one small coil per cylinder along each valve cover. Coil packs, if used, may sit at the front, rear, or top of the engine.

Boxer/Flat Engines (e.g., Subaru)

Coils sit on the sides of the cylinder heads, sometimes accessed more easily from the wheel well or side of the engine bay.

Exceptions and Special Cases

Not every engine uses ignition coils the same way—or at all. Here’s how to recognize when coils won’t be present or may be placed atypically.

• Diesel engines: No spark plugs, hence no ignition coils.
• Hybrid/EV powertrains: The combustion engine (if present) uses coils per its design; full EVs have no ignition system.
• Rotary engines (e.g., Mazda RX-8): Use multiple coils mounted on brackets near the engine rather than directly over “plugs.”
• High-performance/turbo cars: Coils can be tightly packaged under covers and heat shields; access may require additional component removal.

If your vehicle is a diesel or fully electric, you won’t find coils; if it’s a rotary or tightly packaged performance engine, expect remote brackets or concealed positions requiring extra disassembly.

Safety and Handling Tips

Work on coils only when the engine is cool. Disconnect the negative battery terminal before unplugging coil connectors. Never pull on plug wires by the wire—grip the boot. When reinstalling, ensure boots are clean and dry, and torque mounting bolts to spec to avoid cracking the coil housing.

Symptoms That Help Confirm You’ve Found the Right Parts

Failing coils can cause rough idle, misfire codes (e.g., P030X for COP systems), hard starts, and poor acceleration. On COP systems, unplugging a suspect coil (with the engine off) and swapping it to another cylinder can help confirm the fault if the misfire follows.

Bottom Line

Most modern vehicles place ignition coils directly over each spark plug on the cylinder head. If not there, look for a small coil per cylinder on the valve cover with short leads, or a multi-tower coil pack on the engine or firewall. Older cars may have a single coil feeding a distributor, while diesels and EVs won’t have ignition coils at all.

Summary

Ignition coils live either on top of the spark plugs (coil-on-plug), on or near the valve covers with short leads (coil-near-plug), grouped in a pack on the engine or firewall (wasted-spark), or as a single unit on older distributor systems. Remove engine covers and trace plug leads or connectors along the cylinder head(s) to locate them; diesel engines and full EVs don’t use ignition coils.

How much does it cost to replace an ignition coil?

Replacing an ignition coil can cost anywhere from $130 to over $600, with most jobs falling in the $200 to $330 range. This total includes the cost of the coil, which varies significantly by make and model, ranging from about $25 to over $300 for a single coil. Labor costs add an additional $75 to $150 per hour, with the overall time depending on the vehicle’s design.
 
Factors influencing cost

• Vehicle Make and Model: Prices for parts and labor vary by year, make, and model. Luxury or imported vehicles often cost more to repair. 
• Coil Type: Different types of ignition coils exist, with some, like coil-on-plug and distributorless system coils, costing more than traditional ones. 
• Parts Quality: OEM (Original Equipment Manufacturer) coils can be more expensive than aftermarket options, though they are often recommended for certain vehicles. 
• Labor Rates: Shop rates differ, so getting quotes from multiple repair facilities is a good idea. 
• Diagnostic Time: Shops often charge for diagnostic time to accurately identify the faulty coil, which adds to the total cost. 
• Additional Parts: It is sometimes recommended to replace other related parts, like spark plugs, at the same time. 

How to get an accurate estimate

• Use Online Estimators: Tools like those from RepairPal and J.D. Power can provide cost estimates for specific vehicles in your location. 
• Contact a Local Mechanic: For the most accurate quote, contact a reputable local mechanic or dealership to explain the issue and get an estimate for your specific car. 

How do I tell if my ignition coil is bad?

You can tell if your ignition coil is bad by noticing symptoms like a blinking check engine light, engine misfires, sputtering, or difficulty starting. You can also perform a DIY test by disconnecting the coil, inspecting it for damage, using a multimeter to check its resistance, and testing for spark with a spark tester.
 
Symptoms of a Bad Ignition Coil

• Blinking Check Engine Light: This is a serious warning for engine misfires, indicating a potential problem with the ignition system. 
• Engine Misfires or Sputtering: The engine may shake, run rough, or sputter, especially when idling or accelerating. 
• Difficulty Starting: The engine may take longer to crank or start, as the ignition coil struggles to provide a strong enough spark. 
• Loss of Power and Slower Acceleration: A faulty coil can lead to an inefficient combustion process, reducing the power available. 
• Decreased Gas Mileage: Incomplete fuel combustion due to a weak spark can result in wasted fuel, leading to lower fuel economy. 
• Backfiring: The engine may backfire from the tailpipe as it tries and fails to properly burn fuel. 

DIY Coil Testing

1. Visual Inspection: Opens in new tabCheck the ignition coil for any physical damage, cracks, or moisture, as these can lead to failure. 
2. Check for Spark: Opens in new tabRemove the coil and use a spark tester to see if it’s producing a strong, blue spark. A weak, orange, or no spark indicates a problem. 
3. Test Resistance (Multimeter Test): Opens in new tabUse a multimeter to measure the coil’s resistance. Your owner’s manual will have the correct specifications for your vehicle. A reading outside the specified range indicates a bad coil. 

When to See a Professional
If you’re uncomfortable performing these tests or the problem persists, it’s best to consult a qualified mechanic. They can perform a more thorough diagnosis using advanced tools like an oscilloscope or OBD-II scanner to pinpoint the exact cause of the issue.

Is coil ignition easy to replace?

Doing the sparkplugs and coils is not hard, but it takes time. (On 2nd gens) some people say they can sneak one arm behind the motor and get the coils and the plugs out without taking off the plastic and metal cowls, which would make for a quicker job.

Where are ignition coils found?

The location of the ignition coil varies by vehicle, but it is generally found on the engine. You may find a single coil in an older car with a distributor system, a coil pack mounted near the valve cover, or individual Coil-on-Plug (COP) units, where each coil sits directly on top of a spark plug. To find the exact location for your specific car, consult your owner’s manual or a vehicle-specific repair manual.
 
This video shows the location of ignition coils on a typical engine: 48sAuto Repair GuysYouTube · Aug 12, 2022
Types of Ignition Coil Systems and Their Locations

• Older vehicles with distributors: Opens in new tabIn these cars, you’ll find a single ignition coil located either on the engine or inside the distributor itself, connected to the spark plugs by thick rubber wires. 
• Coil packs: Opens in new tabThese systems use a single coil unit that serves multiple cylinders, often found mounted on or near the valve cover. 
• Coil-on-Plug (COP): Opens in new tabThis is the most common system in modern cars, where each spark plug has its own individual coil that sits directly on top of the spark plug. 

How to Find Your Specific Ignition Coil

1. Locate the engine bay: Open the hood of your car. 
2. Identify potential covers: Look for a plastic engine cover, intake tubes, or other components that might need to be removed to gain access. 
3. Search for the specific system:
   • If you have a distributor: Trace the central wire from the distributor cap to the coil. 
   • If you have a coil pack: Look for a larger, box-like unit mounted on the engine. 
   • If you have COP: You’ll see individual coil units, each connected to a spark plug, usually on top of the valve cover. 
4. Consult your owner’s manual: For precise location and specific instructions, refer to your vehicle’s owner’s manual or a repair manual for your car’s make and model.