The BMW E39, the fifth generation of the BMW 5 Series, remains a fan favourite and one of the most celebrated vehicles in the brand’s history. This mid-size luxury saloon was produced from 1995 to 2004 and offered exceptional performance, comfort, and engineering excellence. However, like any car, it is not immune to specific issues. For prospective buyers, owners, and enthusiasts, awareness of the common problems associated with the BMW E39 can help in maintenance and troubleshooting.
This article will delve into the most frequently reported problems with the BMW E39, focusing on its engine, transmission, electrical system, suspension, and general wear and tear. We’ll also discuss preventive measures and maintenance tips to keep this iconic vehicle running smoothly.
Table of Contents
Engine Issues
The BMW E39 is celebrated for its performance and engineering, but like any ageing vehicle, it’s not immune to engine-related problems. Understanding these common issues can help you maintain your E39’s performance and reliability.
VANOS Problems
The Variable Valve Timing system, or VANOS, is used in many BMW engines, including those in the E39. VANOS helps optimise engine performance by adjusting the timing of the intake and exhaust valves. However, over time, the VANOS system can develop faults. The most common issues include a failure of the VANOS seals, which can lead to a loss of power, rough idling, and poor fuel economy. Sometimes, the VANOS solenoids can also fail, triggering engine warning lights.
Symptoms of VANOS Problems
- Reduced engine performance and power
- Poor fuel efficiency
- Engine warning lights on the dashboard
- Rough or uneven idle
Cooling System Failures
BMW E39 owners frequently report problems with the cooling system. The most common issue is the failure of the radiator, water pump, and thermostat. These components wear out over time, especially on vehicles with higher mileage. A faulty water pump or radiator can lead to overheating, which, if left unchecked, can result in severe engine damage.
Symptoms of Cooling System Issues
- Overheating engine (temperature gauge in the red zone)
- Coolant leaks
- Steam coming from the engine
- Low coolant levels
Replacing the water pump and thermostat is essential for routine maintenance. Additionally, some owners replace the radiator with an upgraded model to ensure long-term reliability.
Oil Leaks
Oil leaks are another common issue with the BMW E39, particularly in the M52 and M54 engine variants. The gaskets and seals around the engine can wear out over time, leading to oil drips on the ground. While minor leaks can be relatively harmless, larger leaks can cause a significant loss of oil, leading to engine damage. Common areas affected include the valve cover gasket and the oil filter housing gasket.
Symptoms of Oil Leaks
- Visible oil spots under the car
- Low oil levels
- Oil smell coming from the engine
Regularly checking the oil levels and replacing gaskets can prevent more serious issues.
Transmission Problems
The BMW E39 is renowned for its performance and smooth driving dynamics, but its transmission system is not without flaws. Transmission issues are common, particularly as these vehicles age and accumulate higher mileage. Addressing these problems promptly can help maintain the E39’s reliability and performance.
Automatic Transmission Failure
The automatic transmission in the BMW E39, particularly the ZF 5HP19 gearbox, has been known to fail prematurely. This is typically caused by fluid degradation or the failure of key components, such as the solenoids, valves, or the torque converter. Symptoms of automatic transmission problems include rough shifting, hesitation, slipping gears, or an illuminated transmission warning light.
To prevent transmission failure, it’s important to:
- Regularly check the transmission fluid levels
- Replace the transmission fluid at the recommended intervals
- Address any issues promptly to avoid further damage
Clutch Issues (Manual Transmission)
The BMW E39’s manual transmission models are less prone to issues than their automatic counterparts, but clutch wear can still be a problem, especially in heavily used cars. A slipping clutch, difficult gear changes, or a vibrating clutch pedal are common signs that the clutch may need to be replaced.
To maintain the clutch:
- Avoid riding the clutch pedal unnecessarily
- Change the clutch fluid regularly
- Be aware of the signs of a failing clutch and replace it when necessary
Electrical and Electronics Issues
The BMW E39, while a marvel of engineering, is known for its age-related electrical and electronics problems. As these vehicles rely heavily on electronic systems for various functions, ageing components and wiring can lead to several issues. Understanding and addressing these problems can help maintain the functionality and reliability of your E39.
Electrical Gremlins
One of the most frequently reported issues with the BMW E39 involves electrical gremlins. These can range from problems with the central locking system to issues with the windows and lights. Common problems include malfunctioning window regulators, preventing windows from going up or down correctly. The E39’s electrical control modules (ECUs) can sometimes fail, leading to various electrical issues.
Symptoms of Electrical Problems
- Unresponsive windows or central locking
- Flickering or non-functioning lights
- Intermittent dashboard warning lights
Regular maintenance of the vehicle’s electrical components and checking fuses can help identify and fix these issues before they become significant problems.
Faulty Instrument Cluster
The BMW E39’s instrument cluster is known for developing faults, especially in older models. The most common issue is LCD pixelation, which makes it challenging to read dashboard information. This can be particularly annoying, affecting critical information such as speed, fuel level, and warning lights.
How to address faulty instrument clusters:
- Replacing the defective display panel is the typical solution
- In some cases, the entire instrument cluster may need to be replaced
Battery Drain
A common issue with the BMW E39 is excessive battery drain, which can be caused by malfunctioning electrical components. This could be an issue with the alternator, the battery, or an electrical fault causing a parasitic draw.
Symptoms of Battery Drain
- A dead battery after the car has been left idle for a while
- Difficulty starting the vehicle
- Dim or flickering lights when the engine is off
Regular battery checks and addressing any electrical faults as soon as they are detected can help prevent this issue.
Suspension and Steering
The suspension and steering systems in the BMW E39 are crucial for its renowned driving dynamics, but age and wear can lead to several common problems. These issues can impact handling, ride comfort, and overall safety, making timely diagnosis and repair essential.
Front Suspension Bushings
The front suspension of the BMW E39 is known for experiencing premature wear on the control arm bushings and ball joints. This can lead to a noisy, uncomfortable ride and poor handling. Worn suspension components can also cause uneven tyre wear.
Symptoms of Worn Suspension Bushings
- Clunking or knocking noises when driving over bumps
- Poor handling or excessive body roll
- Uneven tyre wear
Replacing worn suspension components with high-quality parts can restore ride comfort and handling.
Steering Rack Leaks
The BMW E39’s steering rack is prone to developing leaks over time. If the power steering fluid levels drop, steering can become complex, and the steering components will wear out more. In some cases, a leaking steering rack may need to be replaced.
Symptoms of steering rack issues include:
- Difficulty steering, especially at low speeds
- Power steering fluid leaks on the ground
- Whining noises from the power steering system
Regularly inspecting the steering system and promptly addressing leaks can prevent steering problems.
Other Common Issues
In addition to engine, transmission, and suspension problems, the BMW E39 is prone to several other issues that can affect its reliability and ownership experience. These problems often arise due to the vehicle’s age and complexity but can be addressed with timely maintenance and repairs.
Window Regulators
The BMW E39 is notorious for its window regulator issues. Over time, the plastic clips that hold the window in place can break, causing the window to become stuck or fall inside the door. Replacing the faulty regulator can be expensive, but it is a common issue for many E39 owners.
Door Lock Mechanisms
Problems with the central locking system are also common, especially with the door lock actuators. These components can fail, causing doors to lock or unlock intermittently. In some cases, the central locking system may stop working altogether.
Preventive Maintenance and Tips
To ensure that your BMW E39 runs smoothly and reliably, it’s essential to stay on top of regular maintenance. Here are some tips:
- Oil Changes: Regular oil changes are critical to running the engine smoothly. Make sure to use the correct grade of oil and change it at the recommended intervals.
- Cooling System: Check and replace the radiator, water pump, and thermostat regularly, especially if the car is approaching high mileage.
- Suspension: Regularly inspect the suspension components for wear and tear and replace any worn parts.
- Transmission Fluid: To avoid premature wear, replace the fluid in automatic transmission models every 30,000 to 60,000 miles.
- Electrical Components: Monitor the electrical system, checking fuses, wiring, and connectors to prevent electrical issues.
Conclusion
The BMW E39 is a highly regarded luxury saloon that offers a fantastic driving experience, but like any car, it is not free from common issues. Awareness of these potential problems, including engine, transmission, electrical, suspension, and general wear and tear issues, can help you maintain your E39 in excellent condition.
By maintaining preventive maintenance and addressing any issues promptly, you can enjoy the performance, comfort, and reliability that made the BMW E39 such a beloved model.