How do I know if my PCV valve is bad on my Subaru Forester?
If your Subaru Forester is experiencing issues like rough idling, decreased fuel efficiency, or excessive oil consumption, it could be a sign of a bad PCV (Positive Crankcase Ventilation) valve. The PCV valve is a crucial component in your vehicle's emissions control system, and a malfunctioning valve can lead to various problems. In this article, we'll explore the signs of a bad PCV valve and provide steps to help you determine if it needs replacement.
What is the PCV Valve and What Does It Do?
The PCV valve is a one-way valve that regulates the flow of crankcase vapors from the engine's crankcase back into the intake system. This helps to prevent these vapors from being released into the atmosphere, which is important for environmental and emissions control reasons. The PCV valve opens and closes to maintain the proper pressure balance in the crankcase, ensuring efficient engine operation and reducing oil consumption.
Signs of a Bad PCV Valve in a Subaru Forester
Here are some common symptoms that may indicate a problem with the PCV valve in your Subaru Forester:
- Rough Idling: A faulty PCV valve can cause the engine to idle roughly or unevenly, as the improper pressure balance affects the air-fuel mixture.
- Decreased Fuel Efficiency: A stuck-open PCV valve can allow excess air to enter the engine, leading to a lean air-fuel mixture and reduced fuel efficiency.
- Excessive Oil Consumption: If the PCV valve is stuck closed, it can prevent crankcase vapors from being properly vented, causing oil to be pushed past the piston rings and into the combustion chamber, resulting in increased oil consumption.
- Engine Hesitation or Misfiring: A malfunctioning PCV valve can disrupt the engine's air-fuel ratio, leading to hesitation, misfiring, or even stalling.
- Visible Oil Leaks: In some cases, a bad PCV valve can cause oil to leak from the engine's crankcase or other components.
If you notice any of these symptoms in your Subaru Forester, it's a good idea to have the PCV valve inspected and potentially replaced.
How to Check the PCV Valve
Checking the PCV valve on your Subaru Forester is a relatively simple process that you can do at home. Here are the steps:
- Locate the PCV valve, which is typically located on the valve cover or near the intake manifold.
- With the engine running, gently pull on the PCV valve. It should move freely and have some resistance.
- If the valve is stuck or doesn't move, it's likely time to replace it.
- You can also try blowing through the valve - it should allow air to flow in one direction but not the other.
- If the valve is stuck open or closed, or if it doesn't allow air to flow properly, it's a sign that the PCV valve needs to be replaced.
Replacing the PCV valve is a straightforward repair that can be done by most DIY mechanics. Be sure to consult your Subaru Forester's service manual for the specific replacement procedure and any necessary tools or parts.
By understanding the signs of a bad PCV valve and how to properly inspect it, you can help maintain the health and performance of your Subaru Forester's engine.
How often should a Subaru PCV valve be replaced?
The PCV valve is scheduled for cleaning/replacement every 30000 miles. At 120000 miles the hose will be rock hard so replacing both would be a good idea.
How do I know if my Subaru PCV valve is bad?
One very common sign of a bad PCV valve is a whistling or hissing sound coming from the engine. This can indicate that there is a slight blockage in the PCV valve. A Check Engine warning light can be another sign that you need to replace a PCV valve because the PCV valve impacts vehicle performance and emissions.
What is the most unreliable Subaru?
Subarus generally receive high reliability ratings, according to RepairPal. Transmission issues are the most common problem in Subarus. Some Subaru model years have more issues than others, like the 2013 Outback and 2015 WRX.
Is there a recall on Subaru PCV?
Subaru has announced that 205000 vehicles have been affected by a Positive Crankcase Ventilation Valve recall. Subaru of America, Inc. (Subaru) is recalling certain 2017-2018 Impreza and 2018 Crosstrek vehicles equipped with an aluminum Positive Crankcase Ventilation (PCV) valve.
What is the diagnostic code for a bad PCV valve?
For instance, a PCV valve that sticks open may cause a check engine light. The diagnostic trouble codes or DTC will normally not mention the PCV valve. Instead, the diagnostic trouble code P0171 and P0174 are common.
What year are Subaru Foresters being recalled?
2025 Subaru Forester
Subaru has recalled 20,366 Forester SUVs from model year 2025 because their wheels may be defective. The company tells federal safety officials that the wheels may have an “incorrectly specified lug seat surface,” which “could affect vehicle stability, increasing the risk of a crash.”
Is it OK to drive with a bad PCV valve?
It's not advisable to drive with a bad PCV valve because it can cause the gaskets to blow.
What is the most recent Subaru recall?
In late 2022, Subaru of America, Inc. issued a voluntary recall on certain model-year Subaru Ascent SUVs due to a fire risk involving the vehicle's electrical system.
What are the symptoms of a failing PCV valve?
Faulty PCV Valve Symptoms
Here are just some of the symptoms that you might notice: Discolored exhaust gas that is white, black, or blue. A check engine light warning. Rough idling and acceleration.
