BMW N20 Timing Chain Replacement: What You Need to Know

The BMW N20 engine, found in various BMW models, is known for its performance and efficiency. However, one of the most common issues with this engine is the timing chain. In this article, we’ll discuss the BMW N20 timing chain replacement process, including the symptoms, causes, and costs associated with this repair.

BMW N20 Timing Chain Replacement Interval

The recommended BMW N20 timing chain replacement interval is typically around 100,000 miles or 10 years, whichever comes first. However, some N20 engines have experienced premature timing chain wear, leading to the need for replacement much sooner.

It’s crucial to be aware of the symptoms of a failing timing chain and address the issue promptly to prevent further damage to your engine. If you suspect your BMW N20 engine may need a timing chain replacement, consult a trusted BMW specialist or refer to our guide on timing belt and chain repairs.

Symptoms of N20 Timing Chain Failure

Engine Misfires

  • One of the most common symptoms of a failing timing chain in the N20 engine is engine misfires.
  • You may experience rough running, shaking, or a loss of power when accelerating.
  • Misfires can trigger the check engine light, indicating a problem with your vehicle’s ignition or fuel system.

Rattling Noise from the Engine

  • A worn or stretched timing chain can cause a rattling noise from the front of the engine, especially during startup.
  • The noise may increase with engine speed, indicating that the timing chain is not properly tensioned.
  • If left unaddressed, a rattling timing chain can lead to engine damage, as the timing of the camshafts and crankshaft becomes misaligned.

Engine Stalling or Failure to Start

  • In severe cases, a failing timing chain can cause the engine to stall while driving or fail to start altogether.
  • This can be due to the timing chain skipping or jumping, causing the camshafts and crankshaft to lose synchronization.
  • If you experience sudden engine stalling or difficulty starting your BMW with an N20 engine, it’s essential to have the timing chain inspected immediately.

Reduced Engine Performance

  • As the timing chain wears and stretches, it can affect the overall performance of your N20 engine.
  • You may notice a decrease in power, acceleration, and fuel efficiency as the timing becomes less precise.
  • Reduced engine performance can also be a sign of other issues, such as ignition system problems or fuel system malfunctions, so it’s essential to have your vehicle properly diagnosed.

Causes of N20 Timing Chain Failure

Several factors can contribute to premature timing chain wear and failure in the BMW N20 engine:

  • Inadequate Lubrication: Low oil levels or infrequent oil changes can lead to insufficient lubrication of the timing chain, causing increased friction and wear.
  • Faulty Timing Chain Components: Defective timing chain tensioners or guides can cause the chain to become loose or misaligned, leading to premature wear and failure.
  • High Mileage and Age: As the N20 engine accumulates miles and years of service, the timing chain components naturally wear down, increasing the likelihood of failure.

BMW N20 Timing Chain Replacement Cost

The cost of replacing the timing chain on a BMW N20 engine can vary depending on factors such as location, labor rates, and the extent of the damage. On average, you can expect to pay between $1,500 and $3,000 for a complete N20 timing chain replacement.

It’s important to note that neglecting a failing timing chain can lead to more severe engine damage, such as bent valves or a damaged cylinder head, which can significantly increase repair costs. If you suspect your N20 engine may need a timing chain replacement, it’s crucial to address the issue promptly to minimize the risk of further damage.

Diagnosing N20 Timing Chain Issues

If you suspect your BMW N20 engine may have a timing chain problem, there are several steps you can take to diagnose the issue:

  • Listen for Abnormal Noises: Pay attention to any rattling, whining, or ticking sounds coming from the front of the engine, especially during startup and acceleration.
  • Check for Engine Misfires: If your engine is misfiring or running roughly, it could indicate a timing chain issue. Use an OBD-II scanner to check for misfire-related trouble codes.
  • Monitor Engine Performance: Keep an eye out for decreased power, acceleration, or fuel efficiency, as these can be signs of a stretched or worn timing chain.
  • Inspect Oil Levels and Condition: Regularly check your engine oil level and condition. Low oil levels or contaminated oil can contribute to timing chain wear.
  • Consult a Professional: If you’re unsure about diagnosing or repairing your N20 timing chain, consult a trusted BMW specialist or mechanic for expert advice and service.

Preventing N20 Timing Chain Issues

To help prevent premature timing chain wear and failure in your BMW N20 engine, follow these tips:

  • Regular Oil Changes: Maintain a consistent oil change schedule using the recommended oil type and viscosity for your N20 engine.
  • Address Leaks Promptly: If you notice any oil leaks, have them repaired promptly to ensure adequate lubrication of the timing chain and other engine components.
  • Keep Up with Maintenance: Follow your BMW’s recommended maintenance schedule, including regular inspections of the timing chain and related components.
  • Use High-Quality Parts: When replacing the timing chain or any other engine components, use high-quality, OEM-grade parts to ensure reliability and longevity.


The BMW N20 engine’s timing chain is a critical component that requires regular maintenance and attention. By understanding the symptoms, causes, and prevention methods for N20 timing chain issues, you can help extend the life of your engine and avoid costly repairs.

If you suspect your N20 engine may need a timing chain replacement or are experiencing any of the symptoms mentioned above, consult a trusted BMW specialist or mechanic for expert diagnosis and repair. Addressing timing chain issues promptly can save you time, money, and frustration in the long run.

If you’re in need of a replacement N20 engine or other BMW components, trust Engine Finder to help you find BMW and F30 engines for sale from reliable engine importers and scrap yards across South Africa.


craig sandeman rotated

Drawing from extensive expertise in the used car parts industry, Craig Sandeman has established himself as a trusted authority in automotive repair. He possesses a deep knowledge of the challenges encountered by individuals seeking reliable car parts, making him a highly sought-after expert in this field.


Potential issues, causes, and solutions have been identified in the above article based on the experiences of car owners and repairers, as well as web materials such as forum blogs and technical support bulletins. This data is supplied exclusively for the purpose of reference. Only appropriately qualified persons should perform repairs and/or changes on your vehicles.

While it’s important to keep in mind, it’s also important to note that the amount of times anything is mentioned here should not be seen as a sign of its reliability or frequency. Various owners, driving in different ways, and caring for their vehicles in distinct ways will cause two identical vehicles to perform differently.

As previously said, this material is supplied primarily for reference reasons; nonetheless, we hope that by doing so, we will be able to supply you with essential knowledge that will allow you to make informed decisions whenever you encounter any of the aforementioned setbacks.

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