When it comes to driving a BMW, there’s no denying the luxury and performance that comes with this German-engineered vehicle. However, like any other car, BMWs can sometimes experience issues that may result in the appearance of the dreaded engine malfunction light.
This comprehensive guide aims to help you understand the common causes of a BMW engine malfunction light, what it means, and how to address the issue.
Table of Contents
Introduction to BMW Engine Malfunction Light
The check engine light in a BMW is designed to let you know that something is not right with your vehicle and requires attention.
While the issue could be as simple as a loose gas cap or as serious as a failing catalytic converter, it is essential to take precautionary measures and find out exactly what is causing the light to turn on.
Common Causes of BMW Engine Malfunction Light
Loose or damaged gas cap
One of the most straightforward and easily fixable issues that can cause the check engine light to turn on is a loose or damaged gas cap.
A gas cap that is not properly tightened or missing can reduce fuel pressure and allow fuel vapors to escape, reducing fuel economy and increasing harmful emissions.
Failing catalytic converter
A failing catalytic converter can cause the check engine light to turn on. The catalytic converter is a vital part of the emissions system that removes toxic carbon monoxide from the exhaust gases.
A failing or clogged catalytic converter can severely impact fuel economy, and vehicle performance, and even cause damage to other engine components. To fix this issue, the catalytic converter should be replaced.
Fouled spark plugs or spark plug wires
Over time, your BMW will eventually need new spark plugs or spark plug wires. Fouled spark plugs or wires can cause your engine to misfire, reducing fuel economy, and performance, and even preventing it from running altogether. To resolve this issue, replace the spark plugs and wires as needed.
Faulty oxygen sensor
A faulty oxygen sensor can cause the check engine light to turn on. The oxygen sensor provides vital air-fuel mixture information to the engine control unit (ECU).
If the oxygen sensor fails, it can cause the vehicle’s computer to supply the engine with too much or too little fuel, leading to potential engine damage or excessive emissions.
Faulty mass airflow sensor
A faulty mass airflow sensor can cause the check engine light to turn on. The mass airflow sensor measures the amount of air entering the engine and helps ensure the proper air-fuel mixture.
A faulty mass airflow sensor can cause your engine to misfire, ultimately causing poor fuel economy, and performance, and potentially more unnecessary damage to your engine. To fix this issue, replace the faulty mass airflow sensor.
Engine malfunction reduced power
Another common cause of the check engine light in a BMW is the engine malfunction reduced power warning.
This warning is triggered when the vehicle’s computer (DME module) detects a problem that affects the engine’s performance. Symptoms of this issue include reduced engine power, increased emissions, and reduced output.
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Symptoms of BMW Engine Malfunction Light
When the check engine light turns on in your BMW, it is essential to be aware of the symptoms that may indicate an issue. Some of the most common symptoms include:
- Reduced engine power
- Increased emissions
- Decreased output
- Drivetrain malfunction
- Transmission in limp mode (in some cases)
- Engine light malfunction
What to Do if Your BMW Check Engine Light Comes On
If the check engine light comes on in your BMW, it is important to take the necessary steps to address the issue. Here are some suggestions on what to do if your BMW check engine light comes on:
- Check for obvious issues: Look for any visible problems, such as a loose gas cap or damaged spark plug wires, and address them as necessary.
- Read the fault codes: Use a BMW scanner to read the fault codes stored in the vehicle’s computer. This will help you determine what might be wrong with your BMW and the severity of the issue.
- Schedule a service appointment: If you cannot identify or fix the issue yourself, it is best to schedule a service appointment with a BMW specialist as soon as possible to prevent additional issues.
- Drive cautiously: If the check engine light is on and there is a noticeable performance issue, drive your vehicle cautiously until it can be serviced. Avoid aggressive acceleration, high speeds, and excessive engine loads.
Is it Safe to Drive Your BMW with the Check Engine Light On?
While it may be safe to drive your BMW with the check engine light on in some cases, such as a loose gas cap, it is essential to exercise caution and take the necessary steps to address the issue.
If the check engine light is flashing, this indicates a severe issue, and it is recommended to service your BMW immediately.
If you notice a change in the performance of your vehicle or if the check engine light is continuously on, it is best to bring your BMW in for service as soon as possible to prevent additional issues.
BMW Check Engine Light Codes
When the check engine light comes on in a BMW, it typically stores a fault code in the vehicle’s computer that can be read using a BMW scanner. Some common check engine light codes for BMWs include:
- Transmission issues
- Emissions control issues
- Loose gas cap or missing gas cap
- Old battery
- Bad spark plugs
- Fuel and air metering systems problems
- Computer output circuit issues
- O2 sensor
- Ignition system faults
Read also >> Drivetrain Malfunction: How To Fix? (Step by Step)
Read also >> Engine Emission Malfunction (Signs, Causes + More)
How Many Miles Can You Drive with the Check Engine Light On?
The number of miles you can drive with the check engine light on depends on the severity of the issue. If the cause is a minor problem, such as a loose gas cap, you may be able to drive several miles without any issues.
However, if the issue is more severe, such as a failing catalytic converter, it is essential to address the problem as soon as possible to prevent further damage to your vehicle.
What Could Cause the Check Engine Light to Come On in a BMW?
There are many potential causes for the check engine light to come on in a BMW, ranging from simple issues such as a loose gas cap to more serious problems like a failing catalytic converter. Some of the most common reasons for the check engine light to come on in a BMW include:
- Loose or damaged gas cap
- Failing catalytic converter
- Fouled spark plugs or spark plug wires
- Faulty oxygen sensor
- Faulty mass airflow sensor
- Engine malfunction reduced power
How Much Does it Cost to Get the Engine Light Checked?
The average cost for a check engine light diagnosis and testing is typically between 111. However, some BMW service centers may offer complimentary multi-point inspections and free diagnostics in most cases to help determine the cause of your check engine light.
Will the Check Engine Light Reset Itself?
In some cases, the check engine light on your BMW may turn off if the issue that caused it to turn on is resolved. For example, if the cause of your check engine light coming on was a loose gas cap, tightening the cap may cause the light to turn off.
However, if the issue persists or the light does not turn off after driving several miles, it is essential to consult with a BMW specialist to determine the cause of the problem and have it addressed.
In conclusion, having a thorough understanding of the common causes of a BMW engine malfunction light and how to address them is essential for maintaining the performance and longevity of your vehicle.
By staying aware of potential issues and seeking professional help when needed, you can ensure that your BMW continues to deliver the luxury and performance you expect.
How to Diagnose a Check Engine Light >> Check out the video below: