Do it yourself
Frequently asked questions about cars and motorcycles
Car Tutorial (Do it yourself) Motorcycle Tutorial (Do it yourself) Frequently Asked Questions
  1. Car
    2. :
  2. Audi
    3. :
  3. A4
    4. : Breather unit replacement instructions

Audi A4 - Video tutorial

Model: Audi A4 B6 - Years 2000-2004
Part: Engine
Operation: Breather unit replacement instructions

A small premise to understand the usefulness of the PCV (Positive crankcase ventilation) valve or vent unit: it was introduced to reintroduce the vapors generated by the BLOW-BY phenomenon into the combustion chamber, injecting them into the intake ducts and usually taking them from the valve cover, but also directly from the cylinder block. The blow-by literally means "to blow through" and is the phenomenon that occurs when the gases in the combustion chamber are under maximum pressure and part of them cross the piston rings and reach the lower part of the block. This phenomenon leads to an increase in pressure under the piston crown and throughout the crankcase. The main problem of the blow-by is an increase in pressure under the piston crown, thus generating an obstacle during the descent of the piston itself, with pressure values that rise to the point of being able to switch off the engine: here it is therefore born the need to vent these excess gases. At the beginning the pressure was released into the air, but the big problem is that the gases, passing through the oil, are rich in hydrocarbons and therefore very polluting. The pollution generated by the blow-by has led all manufacturers to make the same choice, namely the re-emission of the vapors into the combustion chamber through the use of a special valve: the PCV valve (Positive crankcase ventilation) which is able to manage the introduction of vapors based on the pressure in the cylinder block and the engine load. Having said this, we understand the importance of keeping the breather unit clean and efficient and if necessary replace it together with the relative ducts (if you use the old ones, clean them well): being made of hard plastic, just heat them with a hair dryer. coachbuilder in order to make them fit perfectly in their respective seats.


Posted on 15 August 2023 by ScegliAuto

    Frequently Asked Questions

    • A4 2007-2016 - How to troubleshoot the engine mounts on the Audi A4 B8? Read Answer
    • A4 2007-2016 - What problems do the engine mounts on the Audi A4 have? Read Answer
    • A4 2007-2016 - How much engine oil goes in an Audi A4 b8 3.0 TDI? Read Answer
    • A4 2014-2023 - How many km can an Audi A4 diesel engine travel? Read Answer
    • A4 2014-2023 - Where is the crankshaft position sensor located on the Audi A4? Read Answer
    • A4 2000-2004 - How many kw does the Audi A4 2001 have? Read Answer

How to open the bonnet of the Volkswagen Polo

Let's see in this short and simple guide the instructions that will allow us to open the bonnet of the Volkswagen Polo. First of all we open the front door, on the driver's side, and start pulling the opening lever of the engine hood, in order to open the lock; then let's move to the front of the vehicle and unhook the tab that we find on the central part, above the manufacturer's emblem, as shown in the video. At this point we block the bonnet with the lateral rod; then we accompany the bonnet down to close it again!

Watch the video!


by ScegliAuto

More videos