The EA888 engine may not be caused by it, but it will definitely cause oil burning if it is broken!

Volkswagen/Audi EA888 second generation oil-gas separator (waste valve) The original car is divided into two versions of high and low power When replacing, just match the original car number!

 

Volkswagen/Audi EA888 second generation oil-gas separator (waste valve)

The original car is divided into two versions of high and low power

When replacing, just match the original car number!

 

 

● Environmental regulations require that the crankcase pressure must be negative, that is, the pressure in the crankcase must be lower than the normal atmospheric pressure to prevent the crankcase gas from being discharged directly into the atmosphere and causing pollution;

● The only difference between high and low power is the negative pressure value, which is determined by the pressure spring in the exhaust valve;

● Mbar is a synonym for millibars, which is the unit of air pressure. One square centimeter is subjected to 1 kilogram of atmospheric pressure, which is called "1 bar". One thousandth of a "bar" is called a "millibar". One standard atmospheric pressure is equal to 1013 millibars, so 100 millibars is roughly equivalent to one tenth of the standard atmospheric pressure;

 

1. High power version

OE number:
06H103495AF=AE=AK=K
Negative pressure value: -100Mbar (millibar)
Normal negative pressure value at idle speed: -115 to -90 mbar

2. Low power version

OE number:
06H103495AB=AC=AD=AH=AJ=B=H=E
Negative pressure value: -25Mbar (millibar)
Normal negative pressure value at idle speed: -28.5 to -18.5 mbar

● If the vacuum is too low, the crankcase leakage or excessive blowby should be checked;

● If the vacuum is too high, the diaphragm and spring in the exhaust valve should be checked, or the exhaust valve should be replaced directly;

 

★ Common fault points of EA888 second generation engine exhaust valve

1. The pressure regulating valve diaphragm is perforated

The original black rubber diaphragm was very easy to age and perforate. Now it has been upgraded to a red diaphragm with a reinforced fiber mesh, which rarely suffers from damage;

2. The oil drain hole is blocked, causing the separated oil to not flow back normally

3. The sealing gasket is aging, resulting in traces of oil leakage around it

★ About engine oil burning

The so-called "oil burning" is actually a common name for "oil consumption exceeding the standard".

The main reasons for EA888 oil burning:

 

1. Valve oil seal aging and damage

Valve oil seal has two functions:
One is to prevent the mixture in the combustion chamber or the exhaust gas after combustion from leaking;
The other is to prevent the engine oil from entering the combustion chamber and participating in the combustion;
Therefore, once the valve oil seal has a poor seal, it will cause the cylinder pressure to drop and the problem of "burning engine oil".

2. Decreased sealing performance of piston rings

The piston usually has two air rings and one oil ring.
The air ring is used to ensure the seal between the cylinder and the piston, while the oil ring is used to spread and scrape the oil. When the piston moves upward, the oil is applied to the cylinder wall, and when the piston moves downward, the oil is scraped off.
As the piston ring wears, its sealing performance will gradually decrease until the oil can enter the combustion chamber from between the piston ring and the cylinder wall to participate in the combustion. This is the real meaning of "burning oil".

3. Cylinder eccentric wear or severe wear

The piston ring (oil ring) has poor contact with the cylinder wall, and the engine oil rises into the combustion chamber and is burned.

4. Use inferior engine oil and oil filter

Inferior engine oil cannot provide the proper protection for the friction surface, so it will accelerate the wear of engine components. This includes the piston rings and cylinder walls we introduced above. Abnormal wear will accelerate engine aging and cause it to "burn oil" prematurely.

 

5. Abnormal oil pressure

When the oil pressure is too high, it will cause the engine seal to overload, the oil will leak or enter the combustion chamber and burn, resulting in abnormal oil consumption.

The reasons for excessive oil pressure include: oil filter or oil channel blockage, excessive pressure of the pressure limiting valve opening, excessive oil viscosity, etc.

4. The oil-gas separator (exhaust valve) is not completely separated

When the crankcase blowby is too large or the exhaust valve itself fails, the oil-gas mixture cannot be completely separated, causing part of the unseparated oil to be brought into the combustion chamber and burned.

Therefore, replacing the exhaust valve cannot completely solve the problem of burning oil.

When the vehicle burns oil, you can first check the crankcase vacuum and whether the exhaust valve itself is faulty. If it is caused by the exhaust valve, you can replace a new exhaust valve. If it is due to other reasons, you must replace other corresponding accessories.

 

 

 

★ EA888 first generation/second generation engine equipped models

★ EA888 first-generation/second-generation engine ownership in each province
Data as of December 2021

Unit: vehicle