What Causes Crankcase Ventilation Valve Malfunction In BMWs?

Did you find crankcase venting system related error codes after running a diagnostic on your BMW? When the crankcase or PCV valve fails, it can cause several driving problems and even harm your engine if not resolved as soon as possible. The crankcase ventilation system is tasked with the responsibility of eliminating blow-by gases from the crankcase and reintroducing them back into the intake manifold. However, as the vehicle ages, the performance of this component drops due to oil residue or sludge buildup.

When that happens, pressure builds within the crankcase resulting in oil loss, poor engine performance, and more rapid component deterioration. Faults in BMW crankcase ventilation must be diagnosed, and this may be easily done if the root cause is known and understood. Let’s try to find out the major causes of failure in the crankcase valve and look at some steps to resolve this BMW fault.

Causes of Crankcase Ventilation Valve Failure

• Age/Wear: Like virtually every other part of a vehicle, the crankcase valve undergoes wear and tear over time. Continuous opening and closing of the valve creates a deposit on the valve surface and may ultimately cause choking or damage to the valve. Worn-out PCV valve is a common problem in some of the old models of BMWs and its replacement is often recommended.
• Oil Contamination: Some of the oil vapors that are released into the crankcase ventilation system may deposit themselves on the surface of the valve and over time tend to build up. This sludge hampers the ability of the valve to open and close so as to control the crankcase pressure. In addition, when the presence of oil is too much it can lead to the blocking of hoses and connectors that are fixed on the valve and in this way reduces the valve performance.
• Cold Weather Conditions: Whenever temperatures are low, BMW cars are known to have PCV valve issues. Low temperatures make the moisture in the valve freeze and this will lead to blockages or at worst valve failure. This usually happens in areas where the temperature dips very low during the winter season.
• Poor Engine Oil Quality: All the engine components including the crankcase ventilation valve require high-quality engine oil. Using the wrong type of oil or the low-quality one will leave behind a lot of deposits on the valve which finally ends up clogging or choking the valve. BMW engines are compatible with particular synthetic oils, and using the wrong one decreases performance and may cause problems such as PCV valve failure.
• Lack of Regular Maintenance: Like any part of a car engine, the crankcase system needs regular checks to ensure that it stays healthy all the time. Failing to change the oil for example will result in dirty oil and more sludge that will in turn affect the PCV valve. This is the reason why servicing your BMW is important; a well-serviced engine will make components such as the ventilation valve last longer.

Dealing with Crankcase Ventilation Valve Problems

• Professional Diagnosis: If you notice any of the signs mentioned at the start of this article, seek professional help for assessment and solutions. The crankcase ventilation valve is usually placed in areas that are very much inaccessible and replacing it may require the use of some tools and expertise. Only a certified BMW technician will do the job correctly to prevent further damage to your vehicle’s engine.
• Consider Valve Replacement: Sometimes the valve may need to be replaced. While getting the valve replaced might be a little on the expensive side, it is much cheaper than having to repair an engine that has been damaged by the failure of the valve. If your BMW has high mileage or you’ve had recurring problems, it might be best to simply replace the valve.

Who Should You Entrust Your BMW To When Your PCV Malfunctions?

If you are in search of a professional auto service center for diagnosing or replacing the crankcase ventilation valve of your BMW, then, you are in the right place. At Ultimate Bimmer Service, we have spent over 30+ years working on different BMW models. Our mechanics are always ready to assist BMW drivers in and around Carrollton and Dallas, TX, so if you have any problem don’t delay in bringing it to us. By entrusting your car to us, we guarantee that your BMW will receive the best professional treatment it needs. Don’t let a small valve issue become a large problem – contact us today for quality BMW services.

* Black BMW 550i Car image credit goes to: Brandon Woyshnis.