Go-Parts
Cart 0
Your cart is empty
Add an item to see it appear here.
Wrenchy
Go-Parts Garage
Expert guides for diagnosing, troubleshooting, and replacing auto parts Expert guides for diagnosing and replacing auto parts
Browse All Articles →
🎬 Helpful Videos 🛍️ Shop This Part

Choosing the Right Spark Plugs for Your 2006-2012 Mitsubishi Galant

Keep your Galant's engine running smoothly by understanding its specific spark plug needs.

4 minutes to read 2006-2012 Mitsubishi Galant
Difficulty
2/5
Est. Time
1.5 hrs
DIY Doable?
✅ Yes
Shop Labor
$100-$450
⚠️ Drivable, but... — You can drive, but expect poor performance and fuel economy, and risk damaging your catalytic converter if the check engine light is flashing.
Key Takeaways
  • Stick with OEM brands like NGK or Denso for best results; their Iridium plugs offer the longest life and performance.
  • For V6 models, always use high-quality Iridium plugs for the hard-to-reach rear bank to avoid costly repeat labor.
  • If you find oil in the spark plug wells, replace the valve cover and spark plug tube seals at the same time.
  • Most quality aftermarket plugs are pre-gapped; avoid adjusting fine-wire Iridium tips to prevent damage.
Spark plugs are essential for your Galant's engine to start and run. They create a small, powerful spark of electricity inside each cylinder. This spark ignites the mixture of air and fuel, pushing the pistons and creating the power that moves your car. Having the right spark plugs ensures your engine burns fuel efficiently, giving you better performance and gas mileage. For the 2006-2012 Galant, the type of plug can vary depending on if you have the 4-cylinder or V6 engine.

Signs of Failing Spark Plugs

When your spark plugs are wearing out, your Galant will let you know. Ignoring these signs can lead to poor performance and potentially damage other engine parts.

  • Rough Idling: The engine may feel shaky or sound uneven when you're stopped.
  • Trouble Starting: A weak spark makes it harder for the engine to turn over, especially in cold weather.
  • Poor Fuel Economy: Inefficient combustion from worn plugs means your car uses more gas than usual.
  • Engine Misfires: You might feel a hesitation or stumble during acceleration. The check engine light may also flash, often with codes like P0300-P0306.
  • Reduced Acceleration: Your car may feel sluggish and less responsive than normal.

Oil in the Spark Plug Wells?

If you find oil on your old spark plugs or in the tubes they sit in, it's a common sign of a leaking valve cover gasket or spark plug tube seals. This is a frequent issue, especially on higher-mileage Galants. It's best to replace these seals when you change the plugs to prevent the new plugs from being damaged by oil.

🎬 Watch a professional replace a leaking valve cover gasket.

Choosing the Right Aftermarket Spark Plugs

Mitsubishi originally equipped the Galant with high-quality Iridium spark plugs from NGK or Denso. When choosing replacements, you have several options. Aftermarket plugs from these original equipment (OE) brands are an excellent choice, offering the same performance and longevity as the dealer part without the higher price.

Brand Tiers for Your Galant

  • Top Tier (OEM Quality): NGK and Denso are the original manufacturers for Mitsubishi. Their Iridium plugs (like NGK Laser Iridium or Iridium IX, and Denso Iridium Long Life) are highly recommended for both the 4-cylinder and V6 engines. They provide long life, stable performance, and are designed specifically for your engine.
  • Mid-Tier (Reliable Alternatives): Brands like Bosch and Champion offer quality Iridium and Platinum plugs that are a good fit for the Galant. They provide reliable performance and are a solid choice if you're looking for a balance between cost and quality.
  • Economy Tier (Budget-Friendly): Autolite offers copper and platinum plugs that are more affordable. While functional, they won't last as long as Iridium plugs and may need to be changed more frequently, as often as every 30,000 miles. Skyward is a private label brand; its quality can be inconsistent compared to established manufacturers.

A Note on the V6 Engine

The 3.8L V6 engine has three spark plugs on the rear cylinder bank that are located under the upper intake manifold. Replacing them is a much more involved job than the front three or the plugs on the 4-cylinder engine. 🎬 Watch this step-by-step spark plug replacement for 2.4L engines. Because of the high labor involved, it is strongly recommended to use high-quality, long-life Iridium spark plugs (NGK or Denso) to avoid having to do the job again for another 100,000 miles.

🎬 See how to access and replace V6 rear spark plugs.

Cost of New Aftermarket Spark Plugs

Plug Type Price Range (Per Plug) Typical Lifespan
Iridium (NGK, Denso, Bosch) $9 - $22 60,000 - 105,000 miles
Platinum (Champion, Bosch) $6 - $15 up to 60,000 miles
Copper (Autolite) $3 - $8 up to 30,000 miles

Frequently Asked Questions

Do I need to gap my new spark plugs?

Most modern Iridium and Platinum spark plugs come pre-gapped from the factory for your specific vehicle. It's always a good idea to verify the gap with a feeler gauge, but you should not attempt to adjust the gap on a fine-wire Iridium plug, as you can easily break the delicate tip. The recommended gap for most Galant models is around 0.032" to 0.044", depending on the specific plug and engine.

What's the difference between Iridium and Platinum plugs?

Iridium is a harder, more durable material than platinum. This allows Iridium plugs to have a very fine center electrode, which creates a more focused and powerful spark. They last longer and provide more consistent performance over their lifespan compared to platinum plugs. Since your Galant came with Iridium plugs from the factory, it's best to stick with them.

Why is the V6 spark plug job so much harder?

On the 3.8L V6 engine, the upper intake manifold sits directly on top of the rear valve cover, blocking access to the three rear spark plugs and coils. To change these plugs, the entire manifold must be unbolted and removed, which adds significant time and complexity to the job. The front three plugs are easily accessible, just like on the 4-cylinder engine.

Are there any recalls for spark plugs on my Galant?

No, there have been no specific recalls issued by the NHTSA for spark plugs on the 2006-2012 Mitsubishi Galant. Any issues with spark plugs are considered general maintenance items.

2006-2012 Mitsubishi galant 3.8 v6 valve cover spark plug replacement
2006-2012 Mitsubishi galant 3.8 v6 valve cover spark plug replacement
Mitsubishi galant 2006 3.8 Como cambiar bujías y juntas  de árbol de levas o valve cover gasket
Mitsubishi galant 2006 3.8 Como cambiar bujías y juntas de árbol de levas o valve cover gasket
2004 mitsubishi galant
2004 mitsubishi galant
MITSUBISHI GALANT 2009 VALVE COVER GASKET REPLACEMENT
MITSUBISHI GALANT 2009 VALVE COVER GASKET REPLACEMENT
How to Replace Spark Plugs Mitsubishi 2.4L 4 Cylinder Engine - Outlander Mirage Eclipse Galant
How to Replace Spark Plugs Mitsubishi 2.4L 4 Cylinder Engine - Outlander Mirage Eclipse Galant
DTC P0300 2003 Mitsubishi Galant 4 cyl
DTC P0300 2003 Mitsubishi Galant 4 cyl
How to fix P0300 | Random or Multiple Cylinder Misfire Detected
How to fix P0300 | Random or Multiple Cylinder Misfire Detected
Check Engine Light? Misfire Detected - Code P0300 - Ignition Coil Diagnosis
Check Engine Light? Misfire Detected - Code P0300 - Ignition Coil Diagnosis
P0300 Code Fix 10 Common Engine Misfire Symptoms and How to Repair Them Step by Step
P0300 Code Fix 10 Common Engine Misfire Symptoms and How to Repair Them Step by Step
Mitsubishi Galant Spark Plug Replacement
Mitsubishi Galant Spark Plug Replacement
Mitsubishi Galant Valve cover gasket Replacement
Mitsubishi Galant Valve cover gasket Replacement

Technical Specifications

OEM Part Numbers: 1822A002 MN158596

The 2.4L 4-cylinder and 3.8L V6 engines were factory-equipped with Iridium-type spark plugs. The most common replacement is an NGK Laser Iridium plug. The 2.4L engine uses 4 plugs, while the 3.8L V6 uses 6 plugs.

Wrenchy
Article researched & written by
Go-Parts' AI research assistant. Every article is backed by live web research, verified OEM data, and real technician knowledge — so you get accurate, up-to-date information you can trust.
Meet Wrenchy → Updated Apr 19, 2026

The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.

Year Coverage
This article covers the Spark Plug for:
  • Mitsubishi Galant: 2006200720082009201020112012
In this article
🎬 Helpful Videos
Jump to ▴

Email This Guide

We'll send you a link to this article so you can read it later or share it.

Added to cart · Part