BMWs are known for a smooth performance. They have great torque, emit low emissions, and known for good fuel performance. A major reason why BMWs are known for these features is partially due to the VANOS system. The system works to regulate your engine’s fuel intake and exhaust system. Because the VANOS system works with multiple parts of the engine, there could be several problems such as leaking, rattling, cracking, or improper regulation.

Think of a VANOS System like your respiratory system. Your lungs regulate your oxygen intake and CO2 release. The more activity you do, the more oxygen needed and CO2 to be released. If you were to run a mile but only allow so much oxygen in and CO2 to escape, it could make you sluggish or pass out. The VANOS System works much like this.

Blood And Lungs

The VANOS System varies the timing of the valves by moving the position of the camshafts in relation to the drive gear. The relative timing between inlet and exhaust valves is changed depending on speed. At lower engine speeds, the position of the camshaft is moved so the valves are opened later, as this improves idling quality and smooth power development. As the engine speed increases, the valves are opened earlier: this enhances torque, reduces fuel consumption and lowers emissions. At high engine speeds, the valves are opened later again, because this allows full power delivery.

So now that we know how important the VANOS System is for your car, let’s take a look at some of the common symptoms that you may experience with a bad VANOS System.

Check Engine Light

Like most car problems, the check engine light will come on to warn you that there may be a problem. While this could mean many different problems, do not ignore the check engine light since it could mean ignoring a serious problem.

Bogging or Hesitation

When driving your car at slow speeds (under 3,000 RPMs), does it feel like your car wants to stall or lack acceleration? This could be caused by the VANOS system not allowing the right amounts of fuel in and exhaust out.

Loud Idling

Is your engine louder than usual when you stop at a red light? Does the rattle from your engine annoy you when you roll down the windows? This is known as the VANOS rattle, which could be caused by lose gears that are engaged by the VANOS system.

Regardless of any symptoms you may find, the seals on a VANOS system tend to break down. It would be good to have your car taken to a mechanic for an inspection on any leaks or breaks.

#bmwrepair #bmwvanos

If you have any questions or concerns regarding your BMW, please don’t hesitate to give us a call. specializes in European auto repairs and maintenance. We strive to keep our service costs 40% less than dealerships. Schedule your next service or maintenance for your Audi, BMW, Land Rover, Mercedes, MINI Cooper, or Volkswagen with us.

Written by Spotlight Automotive