Signs of Ignition Coil Failure in Your BMW

Ignition coils play a vital role in your BMW’s ignition system. In older models, a single ignition coil used a distributor to send voltage to spark plugs.

Modern vehicles, including BMW, now use a multi ignition coil system. These coils convert the 12V from your BMW’s battery into 40,000V, enough voltage to create the arc to the spark plugs, which makes your car fire and run.

Although BMW is an optimum vehicle, regular servicing is required to keep components such as ignition coils and others running smoothly. Let’s discuss ignition coil failure in your BMW and how to prevent it.

Causes of Ignition Coil Failure

A failure in ignition coils can be caused over time by the heat and vibrations of your engine. Although insulated, as with any electronic part, constant vibration and heat will eventually cause damage. A professional BMW technician can find the tell-tale signs of faulty ignition coils.

The most common cause of ignition coil failure is overvoltage reaching the coil from a faulty spark plug or plug wire. Either will significantly reduce the lifespan of the ignition coil. Bad spark plugs and wires are avoidable as they need to be changed at a specific frequency set by your BMW’s recommendations. Failure to replace plugs and cables during the required frequency will result in higher costs later.

Typical Symptoms of Ignition Coil Failure

• Engine misfires can be caused by ignition coils as the proper voltage required will not cause its matched plug to spark. This may show itself as a rough idle and sputtering of the engine.
• A rough idle is one of the first symptoms your BMW will show when an ignition coil malfunctions. As the coil fails, your engine’s computer system will attempt to adjust for the faulty ignition coil. This results in the rough idle, which will show itself as a heavy vibration from the engine and felt inside the car.
• Loss of power is experienced when an ignition coil failure occurs. Without the spark from the car, you will have one less valve working for your engine, giving your vehicle much less power as the other valves attempt to make up for the loss of horsepower.
• Reduced fuel economy will take place as your car’s computer attempts to maintain the same horsepower. When more fuel is sent to your engine than usual, your vehicle will burn much more fuel than before.
• Engine stalling, in extreme cases, can occur and is related to a rough idle and misfires. As one ignition coil fails, your BMW’s system may not adjust and keep the car running, causing the stall. This may have you stranded on the road needing repair.
• The check engine light indication will be triggered when your BMW recognizes an ignition coil failure is occurring. This is normally caused when a misfire occurs. Have your car serviced by a professional technician if your check engine light is triggered.
• No-start conditions will occur if the ignition coils in your BMW have failed completely. Without the proper voltage, your engine will not have enough fire to start the engine running process. This is an extreme example, but not having your BMW adequately maintained will eventually lead to significant issues.

Avoid Ignition Coil Failure

Ignition coil issues do not have to be a problem for BMW owners if some simple rules are followed, like making sure your car’s scheduled maintenance occurs according to the manufacturer’s recommendations. Skipping these service appointments not only delays a professional mechanic from finding issues, but they also allow small problems, like causes for ignition coil failure to become more prominent and more costly ones. In the end, you will save much more money by sticking to your car’s plan.

At Hayes European, we combine new-school technology with old-school service to give our customers the quality of attention that saves them money over their BMW’s lifetime. Serving Santa Cruz, Aptos, Soquel, and Capitola, CA, our ASE-certified technicians can troubleshoot and repair ignition coil issues before they turn into a costly repair. Whether BMW or another well built European model vehicle, we have the knowledge and experience to keep your car on the road. Call us today for servicing or repair of your BMW.