How to Replace Spark Plugs on a 2015 BMW i8

How to Replace Spark Plugs on a 2015 BMW i8 (And the Tools You’ll Need)

The 2015 BMW i8 is a hybrid supercar that combines innovation, luxury, and performance in a truly unique package. But like all combustion engines, even this cutting-edge vehicle requires routine maintenance—spark plug replacement being one of the most essential. Failing spark plugs can lead to poor fuel economy, rough idling, misfires, and even long-term engine damage if not addressed in time.

If you're a DIY enthusiast or simply want to understand what goes into changing the spark plugs on a BMW i8, we’ve outlined the tools you’ll need and the step-by-step process. And if it sounds like more than you want to tackle, we offer a mobile solution with ASE-certified technicians who can do the job right in your driveway.

Tools You Need to Replace Spark Plugs on a 2015 BMW i8

Replacing the spark plugs on a BMW i8 is a bit more involved than on a standard vehicle due to its compact engine bay and hybrid layout. Here’s what you’ll need:

  • OEM-quality spark plugs (BMW recommends NGK or Bosch plugs for the i8)

  • Torque wrench (essential for proper tightening)

  • 3/8" or 1/2" ratchet

  • Spark plug socket (with rubber insert) – usually 14mm

  • Socket extensions and a swivel joint

  • Flathead screwdriver

  • Torx bit set (for engine covers)

  • Compressed air (optional, to blow out debris before removal)

  • Dielectric grease (optional, for boot protection)

How to Change Spark Plugs on a 2015 BMW i8

Step 1: Let the Engine Cool Down
Always allow your engine to cool fully before starting any work under the hood, especially on a hybrid vehicle like the BMW i8.

Step 2: Disconnect the Battery
Safety first—disconnect the battery to prevent any accidental electrical issues, particularly since the i8 contains high-voltage hybrid components.

Step 3: Remove Engine Covers
Use a Torx bit to remove any plastic engine covers that are in the way. The i8’s compact design means space is tight, so give yourself as much room as possible.

Step 4: Locate the Ignition Coils
The 2015 i8’s 1.5L 3-cylinder turbo engine has three ignition coils. Unplug the electrical connectors and gently remove the coils using a flathead screwdriver if needed to loosen them.

Step 5: Remove the Old Spark Plugs
Using your spark plug socket, extension, and ratchet, carefully loosen and remove each plug. Be sure there’s no debris in the well before removal—use compressed air if needed.

Step 6: Install New Spark Plugs
Carefully thread the new spark plugs by hand first to avoid cross-threading. Then tighten them using a torque wrench to the factory-specified setting—typically around 23 Nm (17 ft-lb) for the i8. Avoid over-tightening, which can damage the cylinder head.

Step 7: Reinstall Ignition Coils and Covers
Apply a small amount of dielectric grease to the inside of the coil boots (optional), reinstall the coils, plug in the connectors, and reattach all engine covers.

Step 8: Reconnect the Battery and Test the Engine
Reconnect the battery, start the engine, and listen for smooth operation. A well-running i8 should idle smoothly with no warning lights or misfires.

Why Let a Pro Handle It?

While it’s possible to replace spark plugs yourself, the BMW i8’s hybrid system and tight engine bay can make it more complex than most vehicles. Improper torque, damaged threads, or mishandled coils can lead to costly repairs.

That’s why we offer a convenient mobile solution. Our ASE-certified technicians specialize in hybrid and European vehicles like the BMW i8. They come to your home fully equipped to handle the job safely, quickly, and correctly—saving you time, stress, and even thousands in potential dealership labor costs.

Mobile Spark Plug Replacement at Your Home

If you’re in Apple Valley, Burnsville, or surrounding areas, we bring expert-level service directly to your driveway. No towing, no waiting at a shop, and no inflated prices. Simply post your job on our website, describe what your BMW i8 needs, and start receiving estimates from certified mechanics nearby.

We offer same-day service, so you can get back on the road fast—whether it's a simple spark plug swap or a full diagnostic check.