How Understanding BMW Ignition Coils Can Enhance Your Driving Experience

Shariq Khan
Feb 9, 2024
10 min read

European Auto Pro: A Guide for BMW Owners on BMW Ignition Coils

The elegance, precision engineering, and high performance of BMW vehicles are admired worldwide. These iconic German cars, renowned for their exceptional driving experience, rely on various sophisticated components working harmoniously. One such integral part is the ignition coil, a small but mighty component crucial for the smooth running of your BMW.

This comprehensive guide is designed to shed light on the importance of ignition coils in your BMW. We delve into the function of ignition coils, explain how they work specifically in the context of a BMW, explore the aspects tested during a BMW ignition coil examination, and discuss why such a test is crucial. We also provide guidance on the frequency and timing of ignition coil changes and identify the limitations of an ignition coil test.

For those confident enough in their mechanical abilities, we even explain how to change BMW ignition coils at home and discuss advanced changes for performance driving. Furthermore, we estimate the BMW ignition coil replacement cost in South Australia. And finally, we offer a recommendation for a reliable service provider for BMW ignition coil replacement in Adelaide - Euro Auto Pro, located at 253 Goodwood Road, Kings Park, South Australia.

Table of Content:

What is a BMW Ignition Coil?

What is a Ignition Coil?

What is a BMW Ignition Coil?

What Areas Are Tested With A BMW Ignition Coil?

Why Is A BMW Ignition Coil Test Important?

How Often to Have a BMW Ignition Coils Changed?

When to Have a BMW Ignition Coils Changed?

What Can't a BMW Ignition Coil Test For?

Can I Perform a BMW Ignition Coil Change at Home?

How Much Does It Cost For A BMW Ignition Coil Replacement in South Australia?

Conclusion to Our BMW Ignition Coil Guide

Where to Get a BMW Ignition Coil Replacement in Adelaide, South Australia?

Find A BMW Ignition Coil Replacement Specialist Near Me in Adelaide, South Australia

What is a BMW Ignition Coil?

What is an Ignition Coil?

The ignition coil, an often overlooked yet vital component of the modern combustion engine, has a seemingly daunting task. It must take the relatively low voltage generated by your car's battery - typically between 12 to 14 volts - and transform it into a whopping 10,000 to 20,000 volts. This high voltage creates the electric spark needed to ignite the air-fuel mixture in the engine's combustion chambers, driving the pistons down and setting the engine in motion.

An ignition coil does this by way of magnetic induction. The coil consists of two sets of wound wire, known as the primary and secondary windings, around an iron core. When voltage is applied from the battery to the primary windings, it creates a magnetic field. When this field collapses, it induces a high voltage in the secondary windings, which is then directed to the spark plugs to create the ignition spark.

The ignition coil is the heart of the ignition system, pumping the necessary voltage to the spark plugs at precisely the right time to facilitate combustion and power the engine. Without it, your car simply wouldn't start.

What is a BMW Ignition Coil?

BMW, a marque renowned for its dedication to performance and engineering precision, designs its ignition coils to meet the exacting demands of its engines. A BMW ignition coil operates under the same principles as any other coil; its role is to transform the battery's low voltage into the high voltage needed to ignite the fuel-air mixture in the combustion chambers.

However, the BMW ignition coil is not a one-size-fits-all component. These coils are meticulously engineered to each BMW model's specific needs and operational conditions. This could range from the number of windings in the coil, the materials used, and even the physical shape and size of the coil. For instance, BMW's high-performance M Series models typically use ignition coils to withstand higher temperatures and provide more consistent energy to meet the engine's demanding performance requirements.

Like most modern ignition coils, the BMW ignition coil employs a coil-on-plug design. This design has an ignition coil directly connected to each spark plug, providing a more efficient and direct transfer of power. It also reduces the chance of energy loss, which can sometimes occur in older, distributor-based ignition systems.

What Areas Are Tested With A BMW Ignition Coil?

Regular testing of your BMW's ignition coils is key to maintaining optimal engine performance and identifying potential issues early. But what does an ignition coil test entail, and which areas are being assessed?

Let's explore:

Primary Resistance: The primary winding of an ignition coil is the part that initially receives voltage from the vehicle's battery. This winding is typically made of thicker wire and has fewer turns than the secondary winding. During a primary resistance test, a multimeter measures the amount of electrical resistance in this winding. If the measured resistance falls outside the manufacturer's specifications, this could indicate an issue with the coil, such as a short or open circuit.
Secondary Resistance: The secondary winding in the ignition coil produces high voltage. It's made from a much thinner wire and has a far greater number of turns than the primary winding. Just as with the primary winding, a multimeter is used to measure the resistance in this winding. Again, if the measured resistance does not match the manufacturer's specifications, it can indicate a problem within the coil.
Coil Output: This test involves measuring the coil's voltage to the spark plugs. As previously mentioned, an ignition coil must generate a significant amount of voltage (10,000 to 20,000 volts) to ignite the fuel-air mixture. A test light or spark tester is typically used to determine whether the coil produces a sufficient output voltage.
Spark Quality: Beyond just the output voltage, the quality of the spark is also crucial. By observing the spark's colour, sound, and shape, a technician can glean insights into the performance of the ignition coil. A strong, blue spark typically indicates a well-performing coil, while a weak or yellow spark could suggest problems.

Through these tests, a comprehensive assessment of the ignition coil's condition can be made. However, it's important to remember that these tests require specialist knowledge and equipment to conduct accurately and safely.

Why Is A BMW Ignition Coil Test Important?

Testing the ignition coils in your BMW is a critical aspect of vehicle maintenance for several reasons:

Engine Performance: The ignition coil's performance directly impacts the engine's performance. Suppose the coil is not providing a consistent and strong spark. In that case, the engine may not run smoothly, and you may experience problems such as misfiring, rough idling, or a lack of power during acceleration.
Fuel Economy: A weak or inconsistent spark from the ignition coil can lead to incomplete combustion of the air-fuel mixture. This affects engine performance and results in poorer fuel efficiency as the engine needs to work harder to deliver the same amount of power.
Preventative Maintenance: Regular testing can identify potential ignition coil issues before they become more serious. For instance, if the ignition coil begins to fail, it can result in an over-rich fuel mixture, which can cause damage to other parts of the engine, such as the catalytic converter. Early detection allows you to address the issue before it leads to more costly repairs.
Vehicle Safety: A failing ignition coil can lead to a loss of power, which could place you in a dangerous situation while driving, particularly at highway speeds. By testing the ignition coils regularly, you can ensure your vehicle remains safe and reliable on the road.

How Often to Have a BMW Ignition Coils Changed?

Like any vehicle component, ignition coils also have a lifespan and must be replaced over time. A BMW ignition coil should be replaced every 70,000 to 100,000 miles. This is a general guideline, and the interval can depend on your particular BMW model, how you drive, and the conditions under which you drive.

Some high-performance BMW models or those driven more aggressively may require more frequent coil replacements, as the increased engine strain can result in faster wear and tear. Likewise, vehicles regularly driven in harsh conditions - extreme temperatures, stop-start city traffic, or over rough terrains - may also demand more frequent ignition coil replacements.

However, it's worth noting that these figures are averages. In some cases, ignition coils may need to be replaced sooner. Suppose your BMW begins to show symptoms of ignition coil failure. In that case, it's essential to get it checked out by a professional, regardless of the mileage since the last replacement.

When to Have a BMW Ignition Coils Changed?

While it's useful to have a guideline for when to replace your BMW's ignition coils, it's equally important to recognize the symptoms of a failing coil. Ignition coil problems can often present themselves through various signs and symptoms:

Engine Misfires: If your BMW's engine is misfiring, it could be due to a failing ignition coil. You might experience intermittent stuttering or jerking sensations when the engine is running or notice the "Check Engine" light flashing on your dashboard.
Rough Idling or Poor Performance: A faulty ignition coil can disrupt the engine's smooth running, leading to idling vibrations or a noticeable decrease in engine performance, such as a lack of power during acceleration.
Poor Fuel Economy: If the ignition coil isn't working effectively, the air-fuel mixture in your engine's cylinders may not burn efficiently. This can lead to increased fuel consumption and a noticeable decrease in fuel economy.
Difficulty Starting the Vehicle: If your BMW has trouble starting or fails to start, this could be a sign of a faulty ignition coil. This is because the ignition coil provides the spark that ignites the air-fuel mixture in the combustion chambers to start the engine.
Engine Light: If the "Check Engine" light on your dashboard is illuminated, it could be a sign of an ignition coil problem, among other potential issues. Modern vehicles can monitor the ignition system's performance and trigger this warning light if an issue is detected.

If you observe any of these symptoms, having your vehicle inspected by a professional mechanic as soon as possible is advisable. Ignition coil issues can escalate quickly, potentially causing damage to other parts of your vehicle and leading to more expensive repairs.

What Can't a BMW Ignition Coil Test For?

While an ignition coil test can provide valuable insights into the health of your BMW's ignition system, it's important to note that there are limitations to what this test can reveal:

Intermittent Issues: Ignition coils can sometimes fail intermittently, functioning normally and malfunctioning at others. These intermittent issues can be particularly challenging to diagnose, as the coil may appear to function correctly during the test.
Underlying Causes: An ignition coil test can detect a faulty coil, but it won't necessarily identify the root cause of the coil's failure. Factors such as engine heat, vibration, oil contamination, or electrical system issues can all contribute to ignition coil failure. They may need additional diagnostic tests to uncover.
Associated Component Problems: A failing ignition coil can lead to problems in other parts of the vehicle's engine. For instance, a misfiring coil can cause unburned fuel to enter the exhaust system, damaging the catalytic converter over time. While a coil test can detect the failing coil, it can't test for potential issues in other components that may have resulted from the faulty coil.

Remember, while ignition coil testing is an important part of a comprehensive vehicle health check, it doesn't replace a qualified mechanic's need for regular servicing and maintenance checks. Always consult a professional if you suspect any issues with your BMW's ignition coils or other components.

Can I Perform a BMW Ignition Coil Change at Home?

For the mechanically inclined BMW owner, performing an ignition coil change at home is entirely possible, especially given the accessibility of the coil-on-plug design in most BMW models. However, it's important to understand that this task requires mechanical knowledge, the correct tools, and a safe environment to carry out the work.

Here's a simplified breakdown of the process:

Safety First: Disconnect the negative terminal of your BMW's battery to prevent accidental electrical discharge.
Identify and Remove the Faulty Coil: The ignition coils are typically on top of each cylinder. A plastic engine cover often covers them, which you must remove. Once you've identified the faulty coil (using a code reader can help), disconnect it from the electrical connector and remove it from the spark plug.
Install the New Coil: Install the new ignition coil onto the spark plug, ensuring it fits snugly. Reconnect the electrical connector.
Test: Reconnect your battery, start your BMW, and check for any misfires or warning lights. If your vehicle runs smoothly and no warning lights are triggered, the replacement has likely been successful.

While this may sound straightforward, working on your vehicle's engine involves certain risks. Suppose you are uncomfortable with any of these steps or need more tools. In that case, taking your BMW to a professional mechanic is recommended to ensure the job is done correctly and safely.

How Much Does It Cost For A BMW Ignition Coil Replacement in South Australia?

The cost of replacing a BMW ignition coil can vary greatly, depending on your specific BMW model, the quality of the replacement part, and the labour costs of the mechanic or auto service centre performing the work. On average, in South Australia, you can expect a single ignition coil replacement cost, including labour, to range between $150 and AUD 300.

Keep in mind this is an estimate for a single coil. If your BMW requires multiple coils to be replaced, or if you opt for high-performance ignition coils, the cost can be significantly higher. Additionally, the ignition coil failure has damaged other engine parts. In that case, these repairs will add to the total cost.

While the cost may seem substantial, remember that regular maintenance and timely replacement of components like ignition coils can save you money in the long run by preventing more serious and costly damage.

Conclusion to Our BMW Ignition Coil Guide

Ignition coils play a pivotal role in your BMW's overall performance and efficiency. Understanding their function, recognizing symptoms of failure, knowing when to replace them, and understanding the associated costs all contribute to the health and longevity of your vehicle. Ignoring ignition coil problems could lead to more serious engine damage, poor performance, and reduced fuel efficiency.

While you can attempt to replace ignition coils with the required expertise and tools, many prefer to trust professionals' jobs to ensure optimal performance and prevent potential damage.

Where to Get a BMW Ignition Coil Replacement in Adelaide, South Australia?

If you're based in Adelaide, South Australia, and are looking for professional, reliable service for your BMW's ignition coil replacement, consider Euro Auto Pro at 253 Goodwood Road, Kings Park. As specialists in European cars, including BMW, they have the expertise and tools to handle ignition coil tests, replacements, and other associated repairs. Their experienced technicians can provide quality service to keep your BMW running smoothly and efficiently.

In conclusion, the importance of well-functioning ignition coils in your BMW cannot be overstated. Regular testing and timely replacement contribute to a healthy vehicle and a seamless driving experience.

With their expertise in European vehicles, Euro Auto Pro provides a dependable service to ensure your BMW's ignition system and the entire vehicle stays in prime condition. So, Euro Auto Pro has got you covered whether you need a routine check-up, suspect an ignition coil issue, or seek performance upgrades.