Your car's engine needs quality PCV valve to continue in its efficient function. Ensure your car's efficient performance with a top-notch PCV valve.
Engine combustion creates tremendous amounts of energy from the pressurized mixture of air and fuel. But did you know that the engine produces more power than it actually uses? The excess power comes out in the form of exhaust gases. These by-products are actually wasted energy from combustion. If these wastes remain in the engine, it will clog the parts and compromise overall performance. That's why the PCV Valve (Positive Crankcase Ventilation valve) is an important component of your car.
This valve serves as a vent for the upper engine. It prevents unwanted by-products from re-entering from the internal combustion system. It also separates the unwanted by-products from the combustion chamber. After that, the valve funnels the by-products to the exhaust system, where they are guided out of your car through a series of pipes. If it fails, the by-products accumulate in the crankcase, causing your engine to become overworked and worn out.
You can easily diagnose if your PCV Valve is malfunctioning. The first thing to look for is an indication of a malfunctioning air intake system. When the valve is broken, dirt build-ups in your air filter will make your car's fuel consumption inefficient. If that's the case, you should get a PCV valve replacement as soon as possible. Replacements are not expensive, and they can be easily installed. In choosing a replacement, make sure it fits your car specifications and passes OEM standards.
PCV Valve Buyer’s Guide
- The positive crankcase ventilation (PCV) system regulates blowby emissions. It relies on the PCV valve to gather blowby gases from the crankcase.
- This spring-loaded valve contains a tapered pintle that can slide up or down. The sliding pintle can adjust the opening of the valve by changing its position inside the valve housing.
- The PCV valve sucks air and blowby gases out of the crankcase and transports them to the intake manifold. It also removes moisture from the crankcase, extending engine oil lifespan and preventing the formation of sludge.
- PCV valves generally count as maintenance items. Check your valve roughly every 50,000 miles.
- Some of the most familiar issues with the PCV valve include restricted or clogged valves; broken sliding pintles and springs sticking the valve in an open or close position; and damaged PCV hoses.
- Bad PCV valve symptoms include engine oil leaks; engines running lean or rich; rough idling, hard starts, and lean misfires; sludge-related engine damage; and higher emission levels.
- A PCV valve can cost anywhere between $10 and $150. It is sold individually, as part of a PCV repair kit, or as an assembly. Its price tag depends on its brand.
- Take care in selecting the right valve for your vehicle. Even if two valves share the same diameter and hose fittings, their pintle valves and springs may deliver very different airflow performances.
Your vehicle relies on several systems to keep its emission levels within legal limits. One such system is the positive crankcase ventilation (PCV) system. This emission control system regulates blowby emissions, collects fuel vapor from the crankcase, and transports the unburned fuel to the intake manifold.
The PCV system relies on a part called the positive crankcase ventilation valve to gather blowby emissions. If this valve wears out or breaks down, blowby emissions will escape the piston and move into the crankcase. Replace an old or worn PCV valve as soon as possible.
What Is a PCV Valve?
This spring-loaded valve contains a tapered pintle that can slide up or down. The sliding pintle can adjust the opening of the valve by changing its position inside the valve housing.
Depending on the vehicle model and engine, a hose connects the PCV valve to a vacuum port on either the carburetor, intake manifold, or throttle body. These three components connect to the engine and supply the latter with air and fuel.
You can usually find the PCV valve in either a valve cover or the intake valley. Baffles in the cover allow blowby vapors to enter the valve while keeping oil droplets in the crankcase.
What Does a PCV Valve Do?
The PCV system targets blowby emissions, gases that seep through the piston rings and escape into the crankcase. Blowby gases account for roughly 20 percent of a vehicle’s total emissions. As the engine’s piston rings and cylinders get increasingly worn out over the years, the blowby rate increases.
To remove blowby gases from the crankcase, the PCV system pulls air through the breather inlet in the air cleaning housing. The airflow carries blowby gases out of the crankcase and into the PCV valve.
The airflow also removes moisture from the crankcase. By keeping the crankcase dry, the PCV valve extends the lifespan of the engine oil. Getting rid of moisture also prevents acids and sludge from forming in the crankcase. These substances can damage the engine, so the PCV valve extends the engine’s lifespan as well.
The PCV valve controls the airflow from the crankcase to the vacuum port. By moving its sliding pintle down the housing, it increases the volume of air. Conversely, moving up shrinks the opening and reduces the volume of air entering the valve. When the engine runs at higher levels, the PCV valve compensates for the increased blowby gases by increasing airflow.
An operational PCV valve affects the fuel-air mixture in the engine like a vacuum leak in the intake manifold. Your car’s carburetor or fuel injection system compensates for the changing flow of air and blowby gases.
When Should You Replace the PCV Valve?
PCV valves generally count as maintenance items. Check your valve roughly every 50,000 miles and replace it when it shows signs of wear or when you notice symptoms associated with bad valves.
Starting in 2002, many vehicle models with the OBD-II system kept track of the PCV system’s performance. If the flow rate changes because of a bad PCV valve, the powertrain control system (PCM) will switch on the Check Engine Light and log a trouble code.
Earlier OBD-I and OBD-II systems do not monitor the PCV system. However, they check for emission-related issues and will set a trouble code if the bad PCV valve affects the engine’s performance.
Common Problems With the PCV Valve
While PCV valves have long service lives, they can develop problems that reduce their effectiveness. The sliding pintle and spring can break, leaving the valve stuck in just one position. Poor maintenance of the crankcase can also affect the PCV valve.
Some of the most familiar issues with the PCV valve include:
- The PCV valve gets clogged by oil varnish and sludge buildup in the crankcase
- The sliding pintle breaks gets stuck in an open or closed position
- The spring breaks, leaving the pintle stuck open
- Cracked, loose, or leaky PCV hose
Bad PCV Valve Symptoms
The PCV valve is the most crucial part of the PCV system. A problem with the valve will affect the entire emission control system. Bad PCV valve symptoms include:
- Engine oil leaks because of backup pressure forcing the oil through gaskets and seals
- The engine runs lean because the PCV valve got stuck in an open position or a problem with the PCV hose
- Rough idling, hard starts, and lean misfires caused by a lean-running engine
- The engine runs rich due to a loss of airflow from a clogged or broken PCV valve stuck in a closed position
- Engine damage caused by acids and sludge in the crankcase
- Higher emission levels that could lead to failing emission testing
- In OBD-II-equipped vehicles built during 2002 or later, the check engine light illuminates and the PCM logs the associated trouble code
- Pre-2002 OBD-I and OBD-II vehicles will log a trouble code regarding a vacuum leak in the intake manifold
How Much Does a Replacement PCV Valve Cost?
A PCV valve can cost anywhere between $10 and $150. It is sold individually, as part of a PCV repair kit, or as an assembly. Its price tag depends on its brand.
Selecting the Best PCV Valve
While many PCV valves cost relatively little to replace, take care in selecting the right valve for your vehicle. Manufacturers design their valves to deliver an engine-specific flow rate. Even if two valves share the same diameter and hose fittings, their pintle valves and springs may deliver very different airflow performances.
Installing the wrong PCV valve will affect your engine’s performance. A valve that allows too much air to enter the intake manifold will cause a lean fuel-air mixture and associated problems.
Meanwhile, a PCV valve with too little airflow will produce a rich fuel-air mixture. It will also leave more moisture in the crankcase, making it more likely for acids and sludges to build up.
Our website comes with a filter bar to help you find the right PCV valve for your car. Plug in your vehicle’s year, make, and model into the bar to browse our wide offering of replacement PCV valves.
Important Facts You Need to Know About PCV Valve
Like the exhaust manifold, the positive crankcase ventilation (PCV) valve is an important part of your vehicle's exhaust system. So how does the PCV valve work? Engine operations usually generate a considerable amount of high-pressure combustion gases. Piston rings prevent these gases from leaking into the crankcase. These vapors contain moisture, combustion by-products, and unburned fuel vapors. To prevent these gases from building up sludge in the crankcase, the PCV valve draws and directs them into the intake manifold. The intake manifold then allows these gases to be re-burned in the engine's cylinders. Given their functions, PCV valves are usually designed to withstand high pressure and temperature. But just like other exhaust components, the PCV valve will periodically wear out. Good thing, you can easily and conveniently get the best replacement by shopping here at CarParts.com.
• Keeps combustion gases from accumulating in the crankcase
• Prevents moisture that can cause sludge buildup
• Reduces harmful exhaust emissions
Some Important Things to Remember When Buying a PCV Valve for Your Car
The positive crankcase ventilation (PCV) valve is a part of your car's emission system whose main function is to draw out the blow-by gases from the crankcase and send it back into the combustion chamber where it can be burned again. Additionally, the PCV valve also keeps the oil from leaking out and causing sludge. It may be considered as one of the simplest automotive components, but it's still capable of providing chock-full of benefits to your car's performance and the environment. If you're on the look-out for a new PCV valve for your vehicle, here are some of the dos and don'ts to help you pick the right one out:
- Make sure that the size of the PCV valve exactly matches the dimensions of the one you're going to replace. Keep in mind that installing an incorrectly-sized PCV valve may result to improper air flow, which can negatively affect your vehicle's performance.
- Double-check if the flow rate of the PCV valve meets the requirements of your vehicle's engine. Although these components look similar to each other, you shouldn't forget that each of them is rated differently for a specific application.
- Know which type of PCV valve would best suit your car's needs. Consider buying a heated valve if you live in a cold area. Although a lot more costly, this type can effectively prevent freezing problems.
- Ensure that the PCV valve grommet or o-ring attachment is made from high-quality material. Although this component may seem inconsequential, you should bear in mind that this is usually the root of most PCV valve failures.
- Buy an OEM PCV valve instead of going for aftermarket ones to ensure that it fits properly. Aside from compatibility, the quality and reliability of an OEM valve is also better guaranteed.
- DON'T sacrifice quality for the sake of getting a cheap deal. As much as possible, buy an aftermarket PCV valve from well-known brands.
- DON'T forget to inspect the inlet and outlet hoses to see if they need to be replaced as well. It's a good rule of thumb to install new ones along with the PCV valve to ensure that the entire system works properly.
- DON'T settle for a used PCV valve without thoroughly checking if it's in good condition. Make sure that it meets the specifications required by your vehicle.
How to Replace Your Vehicle’s PCV Valve in a Few Easy Steps
The PCV valve basically lessens your vehicle's harmful emissions by feeding the hydrocarbon vapor from the crankcase back into the intake manifold. This component is highly susceptible to clogging, and once it gets plugged up, your engine may have a hard time working properly because of an incorrect oil flow. Stalling and oil leakage are the two infamous indications of this dilemma. Since the PCV valve directly affects your vehicle's engine, it's absolutely important that you replace it once it gets damaged or reaches the manufacturer-recommended replacement schedule. With the right tools and mechanical know-how, you'll be able to perform this as a DIY task. Simply follow the steps below and you'll get this done in jiffy:
Difficulty level: Easy
Tools that you'll need:
- Needle- and angled-nose pliers
- PCV valve replacement
- Ratchet and socket set
- Owner's manual
Step 1: Locate the PCV valve by looking for the valve cover or the plastic tube that's connected to the intake manifold. You may refer to the owner's manual to easily find out where it's located.
Step 2: Using your needle-nose pliers, unplug the plastic tube from the PCV bulb. Remember to work gently to avoid damaging the tube.
Step 3: With your hands, carefully remove the PCV valve from the grommet. If it's hard to do this by hand, you can just use your needle pliers to pry it off. You can also use the angle-nose pliers if the PCV valve is located on an area that's not easily accessible.
Step 4: Before installing the new valve, thoroughly check the condition of the grommet and the plastic tube first. This is to ensure that these components are replaced immediately if they're not in good condition.
Step 5: Take the new PCV valve and put it over the place where you removed the old one earlier. Push down on it firmly until it's securely placed on the rubber grommet.
Step 6: Reconnect the plastic tubes you detached earlier. Make sure all components are properly secured to avoid oil leakage.
The entire task of replacing a PCV valve may take a beginner DIYer around one hour to finish. For expert mechanics, this procedure may be done in just half an hour. Remember to observe proper safety precautions.