Chevrolet Impala Spark Plug Replacement Guide (2014-2020)
Keep your Impala's engine running strong by understanding when and how to replace your spark plugs.
- For the 3.6L V6 engine, replacing the rear spark plugs requires removing the intake manifold, significantly increasing labor time and cost.
- Stick with OEM (ACDelco) or premium aftermarket (NGK, Denso) Iridium spark plugs for the best performance and longevity.
- Modern Iridium plugs are pre-gapped; do not attempt to adjust them as you can easily damage the fine tip.
- A flashing check engine light indicates a serious engine misfire and should be addressed immediately to prevent damage to the catalytic converter.
Is It Time to Change Your Impala's Spark Plugs?
Worn-out spark plugs can cause a number of noticeable problems. If you experience any of these issues, your plugs might be the reason.
- Rough Idling: Your car feels shaky or sounds uneven when stopped.
- Engine Misfires: You may feel a hesitation or stumble from the engine, especially under acceleration. A flashing check engine light is a serious sign of a misfire.
- Poor Acceleration: The car feels sluggish and doesn't have the "get-up-and-go" it used to.
- Worse Gas Mileage: You find yourself filling up the tank more often than usual.
- Difficulty Starting: The engine takes longer to turn over and start.
Engine Warning: 2.5L 4-Cylinder vs. 3.6L V6
Replacing spark plugs on the 2014-2020 Impala is a very different job depending on your engine.
The 2.5L 4-cylinder engine is straightforward. All four spark plugs are easily accessible on top of the engine, making it a great DIY job for beginners.
🎬 Watch this step-by-step guide for the 2.5L 4-cylinder engine.The 3.6L V6 engine is much more difficult. While the front three plugs are easy to reach, the rear three are hidden under the intake manifold. This large engine part must be removed to access them, which significantly increases the labor time and cost. 🎬 See how to remove the intake manifold on the V6. This is a job best left to experienced DIY mechanics or a professional shop.
Choosing the Right Aftermarket Spark Plugs
Your Impala came from the factory with long-lasting Iridium spark plugs. When choosing replacements, it's best to stick with this type for performance and longevity. While cheaper copper plugs exist, they will not last as long or perform as well in this engine.
Brand Quality Tiers
- OEM & Premium Aftermarket (Best Choice): ACDelco is the original equipment manufacturer (OEM) for GM. NGK is also a top-tier choice, and in many cases, they are the actual manufacturer for the ACDelco-branded plugs. Both ACDelco and NGK Iridium plugs are highly recommended and will provide factory performance and longevity. Denso is another excellent Japanese brand known for quality.
- Quality Aftermarket: Brands like Bosch and Champion offer reliable Iridium and Platinum spark plugs that are a good alternative to OEM. They provide good performance and durability.
- Budget-Friendly: Brands like Autolite and Skyward offer more affordable options. While they will work, they may not have the same lifespan or precise performance as the premium brands.
Pro Tip: Modern Iridium spark plugs come pre-gapped from the factory. Do not try to adjust the gap, as you can easily damage the fine Iridium tip. Always install them as they come out of the box.
| Item | 2.5L 4-Cylinder Cost | 3.6L V6 Cost |
|---|---|---|
| Aftermarket Spark Plugs (Set) | $20 - $60 | $30 - $100 |
| Shop Labor Estimate | $100 - $200 | $300 - $500+ |
| Total Estimated Cost | $120 - $260 | $330 - $600+ |
Frequently Asked Questions
When should I replace my Impala's spark plugs?
The manufacturer's recommended service interval is around 97,500 miles. 🎬 Follow this video tutorial to replace your Impala's spark plugs. However, if you experience any failure symptoms, you should have them checked sooner.
Should I replace the ignition coils with the spark plugs?
It is not required, but it can be a good preventative measure, especially on higher-mileage vehicles or the 3.6L V6. On the V6, the labor to access the rear coils is the same as for the plugs, so replacing them at the same time can save you from paying for the same job twice if a coil fails later.
What are the OEM part numbers for my Impala?
Common ACDelco Iridium part numbers are 41-115 for the 2.5L engine and 41-109 for the 3.6L V6 engine. Always confirm the exact part number for your specific vehicle before purchasing.
Are there any recalls for my Impala's spark plugs?
There are no specific recalls for spark plugs on the 2014-2020 Chevrolet Impala. However, there was a major recall for the ignition switch on some model years, which could cause the engine to shut off while driving. It is important to ensure this and any other recalls have been addressed by a dealer.
Helpful Videos
Technical Specifications
OEM Part Numbers: 41-109 41-115 12622561 92457960
The 2014-2020 Impala uses Iridium-tipped spark plugs for a long service life, typically around 100,000 miles. The 2.5L 4-Cylinder commonly uses ACDelco 41-115, while the 3.6L V6 often uses ACDelco 41-109. These plugs are pre-gapped and should not be adjusted.
We Have This Part in Stock
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.
- Chevrolet Impala: