The document explains the Positive Crankcase Ventilation (PCV) system, which is essential for managing crankcase emissions and preventing engine damage by venting gases from the crankcase through a PCV valve. It elaborates on the PCV system's components, common issues arising from its failure, and the significant roles it plays in maintaining engine performance and reducing emissions. Additionally, the document provides guidance on the location, maintenance, and replacement of the PCV system, as well as the tools required for repairs.

1. What Is PCV System?
Wondering about what a PCV system is? Well, Parts Avatar has mentioned all that you need to about the PCV
systems. Internal combustion engines are equipped with crankcase ventilation system (CVS), that is a one way,
pressure-sensitive passage. This enables the natural build-up of gases to pass through the crankcase directly. The
term ‘Blow-by’ is termed as a result of the combustion material that is there in the combustion chamber and blows
past the piston rings and into the rotating assembly's housing. On the other hand, turbocharged engines are
complicated by exhaust leakages from the turbocharger shaft and, in a number of cases, the valve stem seals.
The gases released during the ‘blow-by’, if not oxygenated, condense and combine with the oil vapor that is present
in the crankcase. This further leads to the formation of sludge or leads to the oil becoming diluted with unburnt fuel.
There are fair chances of engine oil leaks past the crankshaft seals and other engine seals and gaskets due to
excessive crankcase pressure. So, it is essential for the crankcase ventilation system to be used as this allows the
blow-by gases to be vented through a PCV (positive crankcase ventilation) valve out of the crankcase.
The process of ventilation mostly leads to the intake manifold enabling the gases to be recirculated before leaving
through the tailpipe. This mechanism completely reduces emissions and is also referred to as a closed-loop CVS,
while an open-loop CVS emits directly to the atmosphere through a filter.
Car Filter PCV System

2. Car Filter PCV System

3. Where PCV System is Located?
Generally, the location of the PCV depends on the type of engine present in the car. If the car has an older
engine without turbo, you can locate the PCV valve on the top or at the side of the valve cover. The valve is
mounted directly on the valve cover on these cars.
So, basically, the PCV valve is mounted somewhere between the intake and the valve cover, so if in case, you
face any difficulty finding it out on the valve cover then we advise you to check any hoses that are connected from
the valve cover to the intake. It is somewhere between these hoses, that you will find the PCV valve.
A number of times, in latest turbo cars, the PCV valve is situated inside the hose. For example, in
Audi/Volkswagen/Skoda/Seat 1.8t, it might be located under the intake inside the hose.
Important Features of PCV System
Some of the important features of the PCV system are:
• It helps in getting rid of crankcase emissions
• Due to constant air circulation, it keeps the system free of moisture
• The systems aids greatly in keeping the engine-damaging sludge to a minimum extend
• The PCV valve also protects the engine greatly during backfires. Well, a backfire, can lead to sudden high-
pressure pulses in the intake manifold. The PCV valves close immediately so that the backfire flame doesn’t
reach the crankcase.

4. Make sure that the PCV system is cleaned otherwise it might lead to deficient airflow. Also, a failed PCV
system can damage the engine as the accumulated pollutants in the engine oil and unrelieved crankcase
pressure can damage the gaskets and seals leading to oil leakages. Even if you don’t maintain your
engine, it might damage the PCV system due to polluted oil sludge.
How Do PCV System Work?
Do know how the PCV system functions? Well, the primary part in the PCV system is the PCV valve, that is
a basic spring-loaded valve with a sliding pintle inside. Inside the valve housing, the pintle is tapered like a
bullet that will help in increasing and decreasing the airflow depending on its position. The up and down
movements of the pintle up change the orifice opening in order to control the volume of the air passing
through the PCV valve. Typically, the PCV valve is situated a valve cover or the intake valley and fits into a
rubber grommet. This location of the PCV valve enables it to pull vapors from inside the engine without
sucking oil from the crankcase. The top of the PCV valve is connected to a vacuum port on the throttle
body through the hose. This aids the vapors to be drained directly into the engine without gumming up the
throttle body or carburetor. When the PCV system pulls air and blowby gases into the intake manifold, it
has a similar effect on the air/fuel mixture as that of a vacuum leak. This is completely made up for by the
calibration of the carburetor or fuel injection system. So, it can be said that the PCV system has no net
effect on the fuel economy, emissions or engine performance.

5. IMPORTANT: It will be useless to remove the PCV system for enhancing the engine
performance. According to the EPA rules, tampering is banned without any emission control
device. Disconnecting PCV system can further lead to moisture accumulation in the
crankcase, thereby resulting into formation of engine-damaging sludge.
Frequent Problems With PCV System
• It can be rightly said that the well being of the engine partly depends on the condition of the
PCV valve. Here we have listed a few frequent problems that you might encounter after
your PCV system fails:
• Increased internal engine pressure
• Damaged oil seals or gaskets
• Engine oil leakages
• There are high chances of moisture and sludge build ups inside the engine
• Engine surging
• Black smoke emissions

6. Symptoms Of Bad PCV System
The positive crankcase ventilation (PCV) valve plays the role of evacuating gas from the crankcase of
the engine. A failed PCV valve can adversely affect the performance of the vehicle, so you gotta watch
out for these symptoms carefully:
• Extra Oil Consumption And Leakage - A failure in the PCV valve may lead to leakages causing
excessive oil consumption. Also, you are likely to notice oil leaking through the seals and dripping
onto the floor. As the pressure in the crankcase increases, the PCV valve fails, so the oil is released
out through the seals and gaskets.
• Dirty filter - Hydrocarbons and oil can contaminate the filter, once the PCV valve gets damaged.
This happens because of an increase in pressure building up in the crankcase that pushes water
vapor through the breather element (filter). This can lead to increased fuel consumption. You can
check this part by inspecting the filter for deposits. Another way is to measure the gas mileage as low
mileage is also an indicator of a failure in the PCV valve.
• Deteriorating performance - You might notice that the performance of your vehicle might
deteriorate day be day. A buildup of pressure in the exhaust not only leads to this but also engine
stalling. Extra oxygen getting into the combustion chamber can lead to the dilution of the air and fuel
mixture further causing the vehicle to run poorly.

7. Tools Needed For PCV System
There are a number of skilled auto mechanics who have a goal of opening their own car
repair shop at some point in their career. But let’s face it; if you want to put up an efficient as
well as profit making shop, then you might need much more than mechanical skills. There are
a number of tools which you might need to perform the car repairs quickly as well as reliably.
Auto repair equipment that you will need to repair your PCV system may include:
● Some needle nose pliers
● Some pliers
● Replacement of the PCV valve
● A screwdriver set
● A wrench set

8. Top Brands For PCV System
When it comes to vehicle owners choice, the brands really matter a lot. You might pay a premium for a
specific car part brand, over time, as it has created a perception of quality, stability as well as trust. There
are some leading car parts brands which are more than just products or services as they give rise to
memories and emotions related with the quality. So have a look at some of the top brands for PCV
system:
• BLUE STREAK (HYGRADE MOTOR) - Starting Price for PCV System From $2 to $288
• FRAM - Starting Price for PCV System From $1 to $7
• DORMAN/HELP - Starting Price for PCV System From $2 to $77
• BECK/ARNLEY - Starting Price for PCV System From $3 to $18
• AUTO 7 - Starting Price for PCV System From $11 to $20
• DORMAN(OE SOLUTIONS) - Starting Price for PCV System From $35 to $61
At PartsAvatar Canada, you’ll will find the best PCV System from top manufacturers of the automotive
market and at the best prices. Visit us now and avail the best offers! We deliver all across Canada and
even have ‘Priority Shipping’ and ‘Free Shipping options’.

9. Related Parts Of PCV System
If you are like most of us, then you won’t know much about the related components of car PCV system fear
not! Here is a quick and easy guide to explain the related parts of the PCV system:
• PCV valve
• PCV valve grommet
• PCV valve screen
• PCV valve hose
• PCV elbow
Total System Costs & Repair Times, Effort For PCV System
Failure in the PCV System comes in a lot of forms. But take note that it is not an inexpensive repair.
Sometimes in the end you might find out that there is a need of complete PCV System replacement. There
is no fast and hard number as to how much would a PCV System replacement would cost as it depends
upon a lot of factors like the brand, make, model as well as the mechanic who is going to repair/replace it.
The cost of replacing a PCV valve varies a lot depending on the engine and. However, the price of the
PCV valve itself is quite cheap, so the prices can be expected to be around 10-100$ for a new valve.

10. How To Change PCV System?
If your PCV valve is jammed with sludge from the pollutants in the exhaust fumes or stuck in the wide-open
position, we recommend that you change it immediately as the PCV valve is an imperative part. The PCV valve is
plugged into a rubber grommet in the valve cover. Locate it on or near the intake manifold.Then you may find a
hose connected to the PCV valve, often kept in place by the clamp. You may also at times find an L-shaped
housing on the end of the hose that covers the end of the valve. Here are the steps you need to follow to remove
the vehicle’ PCV valve:
• Firstly, remove the valve. The ones held with a rubber grommet and can just be pulled out while a number of
them are threaded into place. Try grasping the base of the valve, if you are unscrewing it with your hands. Use
the open ends of a combination wrench or a small crescent wrench, if you don’t use your hands.
• Then check the hose and the hose clamps or grommet by removing the hose and blowing through it. If you find
the hose to be dry, delicate, soft, spongy, full of sludge or hard accumulation, you should change it. When if the
clamps are rusty or the grommet looks damaged, change them.
• Then screw in the new valve using hands to avoid stripping the threads in the valve cover. Ensure that the valve
has been fitted well (note that it should stick only a little when you try to unscrew it). Make sure that you don’t
over tighten these.
• Connect the hose to the PCV valve again and start the engine. Check around the PCV valve for any leakages.