A Guide to Replacing the Ignition Coil on Your 2016-2018 BMW 330i
Experiencing a rough idle or check engine light? Your ignition coils are a likely and easy-to-fix cause.
- Ignition coil failure is a common and easy-to-fix issue on the BMW 330i, typically causing a rough idle and a check engine light with codes P0301-P0304.
- Diagnosis is simple: swap the suspected bad coil with a good one and see if the misfire code moves to the new cylinder.
- Replacement is an excellent DIY job for beginners, requiring basic tools and taking less than an hour.
- For cars over 80,000 miles, it's best to replace all four coils and spark plugs at the same time to ensure reliability and save on future labor.
Understanding the F30 330i Model Years
First, a quick clarification on the vehicle model years. The BMW 330i equipped with the B48 engine was sold in the North American market for the 2016, 2017, and 2018 model years. If you have a 2013-2015 3-series, you likely have a 328i, which uses a different engine and may use different parts. This guide is specifically for the 2016-2018 BMW 330i.
Common Symptoms of a Failing Ignition Coil
When an ignition coil starts to fail on your 330i, the signs are usually very noticeable. Because each cylinder has its own coil, a single failure can disrupt the engine's smooth operation. Look out for these common symptoms:
- Engine Misfires and Rough Idle: This is the most common symptom. You might feel a shuddering, stumbling, or jerking from the engine, which is especially noticeable when you are stopped at a light or accelerating.
- Check Engine Light: A misfire will almost always trigger the check engine light on your dashboard. If you use an OBD-II scanner, you will likely see codes from P0301 to P0304, indicating a misfire in a specific cylinder. A flashing check engine light means the misfire is severe, and you should stop driving to prevent expensive damage to your catalytic converter.
- Loss of Power: With one cylinder not contributing, your car will feel sluggish and less powerful when you try to accelerate.
- Worse Gas Mileage: Your car's computer will try to compensate for the misfire, often by using more fuel, which leads to a noticeable drop in fuel economy.
Pro Tip: How to Diagnose a Bad Coil
If you have a misfire code for a specific cylinder (e.g., P0302 for cylinder 2), you can confirm the coil is the problem with a simple test. Label the suspected bad coil, then swap it with a coil from a working cylinder (e.g., cylinder 3). Clear the engine codes and run the engine. If the code returns as P0303, you know the coil is faulty. If the code stays as P0302, the problem is likely the spark plug or fuel injector in that cylinder.
Choosing the Right Aftermarket Ignition Coil
When shopping for a replacement, you'll find Original Equipment (OEM) and aftermarket options. For BMWs, the original coils are often made by brands like Delphi or Bosch. You can buy these same coils under their own brand name, often for less than the part in a BMW-branded box.
Bremi is a German company that manufactures aftermarket ignition components. They were an OEM supplier for some older BMW models and are generally considered a reliable aftermarket choice, superior to generic, unbranded parts. For the B48 engine in your 330i, Bremi is listed as a direct replacement for the original part. It's a cost-effective option that provides OEM-quality performance.
Important: Don't Mix Brands
It is strongly recommended that you do not mix different brands of ignition coils in your engine. If you are replacing only one coil, be sure it matches the brand of the other three. If you are unsure, or if your car has high mileage, it is best to replace all four coils at the same time.
Known Issues, Recalls, and Service Bulletins
As of early 2026, there are no active recalls or widespread Technical Service Bulletins (TSBs) issued by the National Highway Traffic Safety Administration (NHTSA) for ignition coil failure on the 2016-2018 BMW 330i. Searches for recalls on these vehicles show issues related to other components, but the ignition system has proven to be reliable. You can always check for the most current information by entering your car's VIN on the NHTSA website.
| Part Type | Price Range (Per Coil) |
|---|---|
| New OEM (Genuine BMW) | $60 - $105 |
| New Aftermarket (Bremi) | $57.28 |
| Used OEM | $20 - $40 |
| Shop Labor | $110 - $161 |
Frequently Asked Questions (FAQ)
Is replacing the ignition coil a difficult job?
No, this is a very easy DIY job, perfect for beginners. The coils are located right on top of the engine under a plastic cover. The replacement requires only basic hand tools, like a ratchet and an E-Torx socket, and can be done in under an hour.
Should I replace my spark plugs at the same time?
Yes, it is highly recommended. The ignition coils must be removed to access the spark plugs, so replacing them at the same time costs nothing extra in labor. Worn spark plugs can also cause ignition coils to fail prematurely, so it's good practice to change them together.
Should I replace one coil or all four?
If your car has low mileage (under 80,000 miles), replacing just the one failed coil is acceptable. However, on higher-mileage vehicles, it is wise to replace all four at once. All the coils have been exposed to the same amount of heat and wear, so when one fails, the others are often not far behind.
Do I need to put dielectric grease on the new coil?
Applying a small amount of dielectric grease to the inside of the new coil's boot is recommended but not required. It helps protect against moisture and makes it easier to remove the coil for future service.
Technical Specifications
OEM Part Numbers: 12138643360 12138616153
Direct 'coil-on-plug' ignition coil for BMW B48 4-cylinder engine.
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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.
- BMW 330i:
- 🛍️ Shop This Part
- Understanding the F30 330i Model Years
- Common Symptoms of a Failing Ignition Coil
- Pro Tip: How to Diagnose a Bad Coil
- Choosing the Right Aftermarket Ignition Coil
- Important: Don't Mix Brands
- Known Issues, Recalls, and Service Bulletins
- Frequently Asked Questions (FAQ)
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