Car Troubles? Signs Of A Bad PCV & How To Fix It

You Positive Crankcase Ventilation (PCV) valve is there to help remove excess gases from the engine. This little valve is usually overlooked, but a failed PCV valve can wreak havoc on your engine's performance. The following guide will teach you to identify PCV valve issues and show you how to fix the problem.

Symptoms of a Bad PCV Valve

Look out for the following symptoms:

  1. Sometimes, when the PCV valve fails, the pressure within the engine increases beyond capacity. This is because the valve is not relieving the pressure. The pressure may cause an oil leak throughout various engine compartments, like gaskets or seals.
  2. You may feel acceleration issues due to a dirty air filter. The filter will suffer because the valve is not releasing the gases. The buildup of gases will create a hydrocarbon/oil film that will get stuck to your air filter.
  3. You might feel back pressure, which can translate into a decreased engine performance. There may be stalling issues as well. This is because the valve fails to close, which creates a rich fuel/air mixture.
  4. You might also feel rough idling because of the bad fuel/air mixture mentioned earlier.
  5. The excess of gases could affect your spark plugs, which could burn them prematurely. This is simply because the valve is putting pressure on the spark plugs they cannot handle.

These symptoms are related to a bad PCV valve, but could also be related to other vehicular issues. You can talk to an auto care specialist, such as Mora Chevrolet Buick, if you have questions.

Replacing Your PCV Valve

You will need the following:

  • A new PCV valve that fits your vehicle from your local auto parts store
  • Your owner's manual
  • Safety glasses and gloves


  1. Park the vehicle in a safe and level location.
  2. Let the car cool down long enough to work on it.
  3. Open up your trunk, and put on your gloves and safety glasses.
  4. Locate the PCV valve using your owner's manual. The PCV valve is usually on the passenger side of the engine. It is usually connected to one slightly thick hose that leads to the engine.
  5. Disconnect the negative or red cable from your battery, just for your protection.
  6. Slightly twist the hose, and dislodge it from the PCV valve.
  7. Twist the valve, which should dislodge it. The valve should come out easily.
  8. Replace it with your brand new PCV valve. There should be a clicking sound when you twist it in place.
  9. Reconnect your car battery, and you are done.

As you can see, you can take care of this issue on your own. And you can also save some money.