BMW has been synonymous with luxury since the first vehicle rolled off the production line. In the 1970s, BMW coined the slogan “The Ultimate Driving Machine,” and as a BMW driver, we are sure you would agree.

In reality your BMW is not immune to part failures. The PCV valve is a plastic component which is integral to the functioning of your vehicle. As with most plastic parts, wear and tear is inevitable. It is best to know the signs that your PCV valve has failed so that you can seek immediate professional assistance should this occur.

What is a PCV valve?

The purpose of the Positive Crankcase Ventilation (PCV) valve is to reduce air pollution. Before the 1960s, the crankcase ventilation system removed unwanted gases from the crankcase and released these blow-by gases (unburnt oil and fuel) into the atmosphere.

In 1960, scientists found that automobile engines were a major cause of the smog crisis in California. After much research, the PCV system was designed to send the crankcase gases back to the combustion chamber and reduce air pollution.

Blow-by gases are the leaked, unburnt fuel containing toxic substances left in your vehicle that will wear away any metal components it comes into contact with. Today, all modern vehicles have a PCV valve.

What are the symptoms of a bad PCV valve?

If the PCV valve on your BMW has failed, it could be due to one of two reasons. First, the PCV valve could get clogged or stuck in the closed position. Secondly, it can get stuck in an open position, or a hose can become disconnected, in which case there will be a vacuum leak.

You will notice the following if the PCV valve is clogged or stuck in the closed position.

• Check engine light: The most common sign will be when your check engine light on your dashboard comes on. This light is not present on older vehicles that don’t have an electronic system.
• Increased oil leaks: There will also be oil leaking from the PCV v
• Sludge build-up: When the PCV valve is damaged, it can no longer regulate the intake of gases. The gases subsequently build up and solidify into a sludge, which contaminates the oil in your BMW and causes issues with your engine.
• Black smoke from the exhaust: Normal tailpipe smoke is transparent. If the tailpipe smoke is a different color, it is a clear indication that there is an issue with the engine and potentially the PCV valve. When the PCV valve is stuck in an open position or a hose gets disconnected the following symptoms will be displayed.
• High or rough idle: If you have an idle problem, it’s most likely a faulty PCV valve. A rough idle is identified by shaking and bouncing sensation when the vehicle is in park, when you’re driving, or when you stop at a traffic light.
• Misfires: You may notice that when you are idling or accelerating that the vehicle misfires. If you are unsure what to look out for, your car will feel like there is shaking or hesitation. That is a sure sign the car is misfiring. The check engine light usually comes on when the vehicle misfires as well.
• Increased oil consumption: You will notice that your BMW consumes more oil. There will also be oil in the PCV valve.

What is your next step?

If your vehicle is showing any of the above signs, then it is best to get the PCV valve fixed immediately. Bring your BMW to Swedish Auto Service and one of our trained professionals will ensure that the problem is resolved with little to no inconvenience to you.

We have been the repair center of choice for drivers in Austin since 1993. We are committed to offering the highest-quality service possible without the extended wait times or high costs of the dealerships.

If you are in any of our neighboring cities of Cedar Park, Round Rock, or Leander, visit us at 11008 N Lamar Blvd Austin, TX or call us today to book an appointment at 512-836-0022. We look forward to earning your business.