The BMW M6 is a sporty, high-performance version of the six series that is user-friendly and easy to drive.
However, like any other popular model, the BMW M6 is not perfect.
Since the German performance car is no longer available as a new vehicle, you may want to learn about some of its common problems before buying.
Here is our extensive list of common issues you’re likely to encounter in a BMW M6.
1. Faulty Oil pump damaging the engine
In 2013, BMW M6 owners reported a faulty oil pump issue that could result in catastrophic engine failure without warning.
People reported the problem in BMWM6 Convertible and Coupe models, manufactured between July 19 and September 11, 2012.
The tolerance between the engine oil pump’s driveshaft and the pump’s rotor was not within specification, causing the pump’s driveshaft to separate from the rotor.
If you notice a sudden loss of oil pressure in your vehicle, you may end up dealing with an engine failure problem, increasing the risk of a crash. In extreme cases, you may need to replace your engine.
BMW issued a recall to replace the oil pumps on all the affected vehicles.
If your BMW M6 has this issue, don’t drive it until it has been serviced.
Doing so can damage the engine further, resulting in irreparable damage.
2. Transmission warning light appearing on the dashboard
If you notice a transmission warning light on your dashboard, you’re not alone. Many BMW owners have reported seeing transmission warning lights on their dashboards.
Apart from a transmission warning light, you may also experience:
- Transmission getting stuck in one gear or refusing to shift to certain gears
- Frequent gear slipping
- Noisy when the car is neutral
- Rough transmission shifts
- Gear changes are too erratic, bumping into one or more of the gears
- The car lags when switching gears
All these signs could indicate different problems that need to be checked independently to know the real cause.
The four main causes include:
#1 Leaks in transmission
Seals and gaskets used to keep the transmission fluid inside the transmission system can wear out and fail, leading to transmission fluid leaking. While the leak is mostly internal, you may notice a few droplets on the ground below your car.
How to fix:
You will need to buy and install a new gasket.
#2 Low transmission fluid
Your vehicle’s transmission requires fluid to keep it lubricated and prevent overheating when changing gears.
Your car may run out of transmission fluid due to leakages if it reaches its lifespan or gets damaged.
How to fix:
Refill your transmission fluid regularly or at least every six months.
#3 Blocked transmission fluid filter
As the transmission fluid circulates the transmission system, it collects dirt over time.
To prevent the dirt and debris from affecting transmission operations, your BMW comes with a fluid filter that can also clog with dirt over time.
When clogged, it can block the transmission fluid from circulating in the transmission system, causing overheating and damage to transmission components.
Signs of a clogged filter include:
- Rattling noises
- Burning odor
- Shafting problems
- Noise when the vehicle is in neutral
- Shifting problems
- Challenges reversing
How to fix:
If you’re due for transmission filter maintenance, your technician can flush the transmission fluid, install a new filter and replace the dirty transmission fluid.
The entire service will cost you between $250 and $400, including labor.
#4 Faulty transmission sensor
The transmission typically has two sensors; the input and output. The input sensors monitor the transmission speed, while the output sensor monitors the output shaft speed.
When the transmission sensor is faulty, the sensors may not send the right signals to the vehicle’s powertrain control module.
How to fix:
Determine which sensor is faulty and hire a professional technician to replace it. It will cost you between $300 and $350, including labor.
3. Water leaking into the trunk area
Many BMW M6 owners have reported seeing small puddles of water in the storage area.
The problem is more common in Convertibles, and blocked drainage pipes cause it.
Water may leak into the trunk when the vehicle’s drainage pipes get blocked. If ignored, the water can cause massive damage and cost you thousands of dollars to repair.
Your trunk has several electrical units which can be quite expensive to replace if damaged. Water can also lead to rust.
To fix the problem, you must first locate the drains, find the entrance and flush what’s clogging them.
You can consult your vehicle manual to locate the small drain pipes or call a technician to check them for you and unblock them.
As you do so, check other areas in your vehicle that could trap water, leading to corrosion. To be sure, consider checking all pipes.
4. Power steering light on intermittently
When the electric steering lock indicator light appears, it may also notify you that if the engine is off, it may not restart. You may also notice the steering wheel getting tighter.
While there can be many causes, including a worn out or damaged battery sending mixed signals to the computer, the problem in the BMW M6 has a specific cause related to the puddle of water in the trunk.
If you have changed the battery, but the steering light keeps popping intermittently, you could have a bad trunk seal, allowing water into the part of the trunk near the tail lights.
Since the module that controls the power steering functions is on the back wall of the trunk, the water may have corroded the electrical connections, leading to wrong signals.
Additionally, if you have been putting wet items like iceboxes in your trunk for a long time, water may have made its way into the electrical system and corroded the electrical systems, causing the steering wheel light to come on.
Consider replacing the electrical connections and modules. Have the trunk seal repaired to keep water and any wet material from reaching the vehicle’s electrical systems?
If you’re still experiencing a tight steering wheel, you may want to look at other causes, such as:
#1 Power steering fluid too low
The power steering fluid applies pressure against the piston inside the rack and pinion, forcing your steering to power and function. If this fluid is low, the amount of force required will reduce. When this happens, you may have to rely on your efforts to turn the steering in the right direction as the power in the steering system will be too low.
#2 Damaged power steering belt
The power steering belt drives the action of the steering wheel system. That means the functionality of your steering has controlled the belt. If it snaps, cracks, breaks, or loosens, your steering system may not operate efficiently, and you will have challenges turning the vehicle to different directions.
#3 Damaged steering rack
The steering rack is part of the rack and pinion and a major part of the steering assembly that works with the steering system. The steering rack can wear out over time, making it harder to steer the vehicle. When damaged, you will notice it is only hard to turn when you first turn the vehicle on, as the problem tends to go away when the car warms up.
5. “Drivetrain malfunctioning” massage on the dashboard
Almost all BMW M6 models have experienced the dreaded “Drivetrain malfunction” popping up on their dashboard after starting the vehicle or while driving.
This display is not only dangerous but costly to repair. That’s why you need to call your dealership as soon as you see it and have the vehicle towed for inspection.
A drivetrain malfunctioning message indicates a problem with the engine or transmission.
Your BMW computer may detect the problem immediately after you start the vehicle and may deactivate several functions to prevent you from driving.
In a driving situation, the message may display, and the car may shut down immediately to prevent imminent damage.
A drivetrain malfunction comes with many signs. They include:
- Constant vibration
- Rough idling
- The engine cuts off when the gear is engaged
- The transmission gets stuck in the gear
- The car stops and won’t start
BMW drivetrain malfunction is traceable to multiple causes.
Here are the most commonly reported causes by BMW M6 owners:
Damaged fuel injectors
When one or more fuel injectors are clogged or damaged, it can affect the engine performance as it will lack enough power transfer through the drivetrain to engage the wheels to move.
How to fix:
If the fuel injectors are dead, you should replace them. If clogged, your mechanic can unclog them by removing the injectors and cleaning them thoroughly before installing them.
Bad spark plugs
Faulty or worn-out spark plugs alter the optimal functioning of the BMW’s drivetrain. Worn-out spark plugs can result in different malfunctions, including rough idling, engine misfires, or engine refusal to start.
How to fix:
Faulty spark plugs should be replaced. It’s best to replace the entire set as replacing some can hinder proper functioning.
Faulty fuel pump
If the fuel pump is faulty, it may not supply the right amount of fuel to power the vehicle’s engine to aid proper acceleration.
How to fix:
Replace the fuel pump.
Faulty ignition coil
A faulty ignition coil can result in misfires and cause a drivetrain malfunction error message on your dashboard. If there are misfires, the ignition coil attached to that cylinder could be bad.
How to fix: Swap the problematic coil in that cylinder with another. If the problem persists, replace all the coils.
Clogged catalytic converter
When clogged, the catalytic converter can prevent exhaust gases from releasing appropriately, causing the drivetrain to malfunction on your car’s computer.
How to fix: Pour a catalytic converter cleaner into the fuel tank and drive your vehicle for 30 minutes at 2500 rpm.
This allows the catalytic converter cleaner to go around the car system and clean it. Make sure the vehicle doesn’t overheat.
Low or poor quality fuel
If your car is driving using low or poor-quality fuel, the engine power will likely drop, which alters the proper transfer of engine power through the drivetrain to the wheels.
How to fix: Remove old, poor quality fuel and add fresh, high-quality fuel and start the car.
6. Transmissions stuck in gear
While gear shifting problems are common, they are even more common in the BMW M6 as they are caused by a defective solenoid, torque converter, or limp mode.
The solenoid helps your vehicle shift gears. It powers the starter and allows the computer to detect the speed and determine which gear to engage.
If they fail, solenoids can cause gear to get stuck.
If your torque converter is faulty, your vehicle may get stuck in the first gear.
Since they are usually full of transmission fluid, transmission and torque failure symptoms tend to go hand in hand.
When your vehicle’s computer fails to receive any signal from the solenoid or receives false signals, it activates a safety mode known as a limp mode. Limp mode deactivates the gear, causing it to lock in the third or second gear.
To fix the issue, you will need to replace the faulty part. If your car is still under warranty, you can get it fixed at no charge. If not, you may need to use your savings to replace the pump.
7. Powertrain: Driveshaft poorly welded during manufacturing
The problem resulted from improper welding during manufacturing, causing the driveshaft to fracture and fail.
This can lead to loss of drive to the rear wheels and loss of propulsion.
Additionally, if the car is turned off and exits without a parking brake application, the car may roll.
Both of these conditions can cause a serious crash.
BMW drivers reported this problem in the 2015 BMW M6s manufactured from September 3, 2014, to December 3, 2014. It also affected the 2015 M6 Convertibles and Grand Coupe manufactured during the same period.
If you have a car with this problem, you can take your BMW to your nearest dealership to inspect and replace the driveshaft free of charge.
8. “Check airbag system” light on the dashboard
For many people, a check airbag display on their car screen means the air bag sensor could be faulty, and replacing it works most of the time. However, it’s not the same case if you own a BMW M6.
The 2012 and 2013 BMW M6 Convertibles and Coupe vehicles drivers’ frontal air bag inflator may have been improperly welded.
As a result, the inflator housing could disconnect from the base and cause the metal plate to strike you in the event of a crash.
Since this was a safety recall, you can take your vehicle to your dealership to replace your airbag and module. The recall was issued in 2017.
General Pros and Con for BMW M6
The BMW M6 is well–known for its extraordinary performance. It’s powered by a 4.4 liter, twin-turbo V8 engine that is mated to a seven-speed automatic and six-speed manual transmission. However, like any other vehicle, the M6 also has faults that affect shoppers’ buying behavior.
Pros of the BMW M6
Here are the advantages of the BMW M6:
- Great performance with speedy accelerations
- Aggressive sporty look with a deep front bumper, quad exhausts, and flared arches
- Practical, functional, and comfortable cabin
- Spacious cargo space
- Fitted with multiple driver-assist safety features such as park assist, lane departure warning, pedestrian recognition, and lane changing warning system
Cons of the BMW M6
Here are the common drawbacks of the BMW M6:
- A transmission warning light appears on the dashboard
- Faulty oil pump damaging the engine
- Water leaking into the trunk area
- The power steering light is on intermittently
- “Drivetrain malfunctioning” massage on the dashboard
- Transmissions stuck in gear
- Powertrain: Driveshaft poorly welded during manufacturing
- Check the airbag system light on the dashboard
What Do the Reviews Say About the BMW M6?
“One might not expect such brutish power from a comfortable and cosseting convertible, but that’s exactly why we like it!”
“..The 650i’s turbocharged V8 launches you to the nearest 60 mph within 4.5 seconds, with a formidable 480-pound feet of torque on tap whenever you need to pull out a pass.”
What’s the Resale Value of a BMW M6?
Final Thoughts on BMW M6 Common Problems
The BMW M6 is undoubtedly a good car.
However, like any model, it comes with faults, some of which have been recalled in the past.
If you’re looking forward to buying this car, it’s your responsibility to check if all recalls have been repaired before buying the vehicle.
Get a highly qualified technician to check every component before signing the paperwork.
If you encounter a challenge, feel free to consult this guide for solutions.