Why do BMW M3 throttle actuators fail and what do they cost to replace? EuropowerMotorsports

If you’re curious to learn about BMW M3 throttle actuators, here’s an article we put together on why they end up failing, along with a few places where you can buy a set of them for your car with our discount. You can check out the Europower Motorsports throttle actuators below. Use our code M3List at checkout to see how much you can save.

Click here to see pricing on BMW throttle actuators with discount code “M3List”

Understanding BMW S65 Throttle Actuators: Common Failures and Causes

BMW is renowned for producing high-performance vehicles, and the S65 engine is no exception. Found in the M3 and M4 models from 2007 to 2013, this 4.0-liter V8 engine has gained a reputation for its exhilarating performance and distinctive engine note. However, like any complex machinery, it’s not immune to issues, and one of the common culprits for problems in the S65 engine is the throttle actuator. In this blog post, we will delve into what throttle actuators are, why they fail, and what you can do to prevent or address these failures.

Throttle Actuators 101

Before we dive into the reasons for their failure, let’s first understand what throttle actuators are and why they are crucial components in modern engines.

Throttle actuators are responsible for controlling the throttle valve, which regulates the airflow into the engine. In simpler terms, they dictate how much air is allowed into the engine’s combustion chambers, which, in turn, affects the engine’s performance. These actuators work in concert with other engine management systems, such as the engine control unit (ECU), to ensure precise control of the engine’s air-fuel mixture and power output.

Common Failure Symptoms

Throttle actuators in the BMW S65 engine can exhibit a range of symptoms when they begin to fail. Recognizing these signs early can save you from more significant issues down the road. Some common symptoms of failing throttle actuators include:

1. Reduced Power: One of the most noticeable signs is a sudden loss of power. The engine may feel sluggish and unresponsive, making it difficult to accelerate or maintain consistent speed.
2. Engine Warning Lights: Modern BMWs are equipped with onboard diagnostic systems that can detect issues in real-time. When the throttle actuators malfunction, the engine management system may trigger warning lights on the dashboard, such as the check engine light, reduced power mode, or other related warnings.
3. Rough Idle: Throttle actuator problems can lead to erratic idling, causing the engine to shake or vibrate when at a standstill.
4. Stalling: In severe cases, a malfunctioning throttle actuator can cause the engine to stall, making it impossible to drive.

Now that we’ve identified the symptoms let’s explore the reasons why BMW S65 throttle actuators tend to fail.

Common Causes of Throttle Actuator Failure

1. Wear and Tear: Like any mechanical component, throttle actuators are subject to wear and tear over time. The repeated opening and closing of the throttle valve can lead to mechanical fatigue, causing the actuator to lose its precision and responsiveness.
2. Electrical Issues: Throttle actuators are electronically controlled, and any issues with the electrical components, such as wiring or sensors, can lead to failure. Corrosion, moisture, or damaged connections can disrupt the actuator’s communication with the ECU.
3. Carbon Buildup: Carbon deposits can accumulate on the throttle bodies and actuators over time, affecting their smooth operation. This buildup can hinder the throttle’s movement and lead to performance issues.
4. Software Glitches: Sometimes, the root cause of throttle actuator problems can be related to software issues within the engine control unit. Software glitches or incorrect calibration can result in erratic throttle behavior.

Preventing Throttle Actuator Failures

While some level of wear and tear is inevitable, there are steps you can take to minimize the risk of throttle actuator failures in your BMW S65 engine:

1. Regular Maintenance: Scheduled maintenance, including cleaning and inspecting the throttle bodies, can help prevent carbon buildup and identify issues before they become severe.
2. Quality Parts: If you need to replace a throttle actuator, invest in high-quality OEM or reputable aftermarket parts to ensure longevity and reliability.
3. Professional Diagnostics: If you experience any of the symptoms mentioned earlier, have your vehicle inspected by a qualified BMW technician. Early detection and diagnosis can save you from costly repairs.

Throttle actuator failures in the BMW S65 engine can be frustrating and costly if left unaddressed. However, with proper maintenance and timely intervention, you can enjoy the thrilling performance of your BMW without worrying about throttle actuator problems. Remember that routine check-ups and using quality parts are key to keeping your high-performance engine running smoothly.

The throttle actuator is a common problem for all M3 vehicles with the S65 engine and E6X M5/M6 with the S85 engine. Undoubtedly, German engineering is considered the benchmark for combining design and functionality, but even the best of us make mistakes. The Throttle Actuator design has been a disaster from day one. Every single OEM unit will fail sooner than later. The failure rate of OEM units is 100%. Albeit it is not catastrophic, going into limp mode is never fun. Failure of the throttle actuator will cause the engine to go into ‘limp mode’ with the DSC and EML light illuminated on the instrument cluster. The common faults codes are: ‘2B15 – Throttle Valve Actuator Bank 1′ & 2B16 – Throttle Valve Actuator Bank 2’. 

Euro Power Motorsports Upgraded OEM+ Throttle Actuators have been the first choice for most BMW owners. With these rebuilt throttle actuators, we replace all internal components with higher-rated versions, ensuring that the actuator will not fail again and will outlive the car. We are so confident about our units that we offer them an UNLIMITED MILES LIFETIME WARRANTY. We also offer a Labor Warranty of up to $200.00 if the shop has to do the job again. 

Key Points: 

• Gears upgraded to superior materials,
• All Mosfets replaced.
• Transistors & capacitors checked, Voltage regulators, microprocessor, serial Eprom tested or changed.
• Unlimited Miles Lifetime Warranty
• Labor Warranty of up to $200.00

Click here to see pricing on BMW throttle actuators with discount code “M3List”