Auto Manual of VW Passat B5

VW Passat
The maintenance instruction
1. Maintenance service
- 2. Engines
   2.2. The general information
   2.3. The bottom mudguard of a motor compartment
    2.4. The four-cylinder petrol engine
    2.5. The diesel engine 1,9-I-TDI
    2.6. A drive газораспределительного the mechanism
   - 2.7. The engine 2,8-I-V6
      2.7.2. Removal and installation of a head of the block of cylinders
      2.7.3. Compression check in engine cylinders
      2.7.4. Check of the engine by means of the vacuum gauge
      2.7.5. Removal and installation поликлинового a belt
      2.7.6. The general recommendations about engine oils
      2.7.7. Кругооборот engine oil
      2.7.8. Check of pressure of oil and the gauge of pressure of oil
      2.7.9. Removal and installation of the oil pallet
      2.7.10. Start of the engine after major repairs
      2.7.11. The basic malfunctions at engine start
      2.7.12. The basic malfunctions of system of greasing
3. Cooling system
4. Fuel system
5. Engine management
6. An exhaust system
7. Transmission
8. A running gear
9. A steering
10. Brake system
11. A body
12. Heating, ventilation
13. An electric equipment


2.7.4. Check of the engine by means of the vacuum gauge

Substantive provisions and fluctuations of an arrow of the vacuum gauge at diagnostics of malfunctions of the engine

Using the vacuum gauge, it is possible to receive the information on a condition of the engine and to define that the lining of a head of the block of cylinders is punched, rings are damaged, the power supply system is incorrectly adjusted, valves etc. are damaged. Unfortunately, vacuum gauge indications can be interpreted incorrectly, therefore these measurements are necessary for using only in a combination to other methods of check of the engine. For correct definition are important both absolute value of indications of the vacuum gauge, and speed of their change.

1. Connect the vacuum gauge to an inlet collector. Start and warm up the engine to normal working temperature.
2. Consider vacuum gauge indications. If the engine is in a normal state, vacuum gauge indications should be 430–560 mm Hg, and the arrow вакууммет ра should be at a stop.
Low constant indications of the vacuum gauge testify that the lining between an inlet collector and the throttle case is damaged, the vacuum hose is damaged, the moment of ignition or wrong installation of phases timing is incorrectly established.
If indications of the vacuum gauge below norm on 80–200 mm Hg also fluctuate, that, probably, the lining of an inlet collector near to an entrance aperture is damaged or the injector is faulty.
If indications constantly fall on 50–100 mm Hg rather stably го values, that, probably, valves are damaged. In this case it is necessary to measure a compression in engine cylinders.
If indications fall, but is not regular, that, probably, gets jammed the valve or there is a failure in ignition.
Small fluctuations about 25 mm Hg are usually connected with failures in ignition system.
If indications strongly fluctuate, that, probably, the lining of a head of the block of cylinders or the cylinder is damaged.
If the arrow slowly moves largely values, that, probably, the system of compulsory ventilation картера is littered, the lining of an inlet collector or a lining between the case throttle заслонки and a collector is damaged.
3. Check up, how fast восстанав ливаются indications of the vacuum gauge after sharp and full opening throttle заслонки and its return to a starting position. If the engine is in a normal state, indications fall almost to zero, then increase approximately on 130 mm Hg above norm and again decrease to former values at constant turns of idling. If indications are restored slowly and pass through a maximum after closing throttle заслонки, that, probably, piston rings are damaged. If there is a long delay, that, probably, the exhaust system is littered.