Volkswagen Golf Service & Repair Manual: Checking vacuum generation
 Note
| The average air pressure of the earth's atmosphere at sea
level is 1013 mbar and decreases steeply as the altitude
increases (approx. 100 mbar/1,000 m altitude). Local and time
fluctuations also influence vacuum generation. |
| A cold engine, a switched-on air-conditioning system as well
as engine idling have an adverse influence on generation of a
vacuum. |
| – |
Before starting work, check all vacuum hoses for damage
(e.g. cracks or marten bite) and to check that they are
correctly and firmly attached |
| – |
Connect brake servo vacuum gauge -VAS 6721-
→ Chapter. |
| – |
Open cut-off valve -A-. |
|
|
|
| – |
Close cut-off valves -B+C-. |
| – |
Start warm engine (>60°C), press accelerator briefly (engine
speed above 2,000 rpm). |
| – |
Read indicated measured value. |
| Normally (see notes), the vacuum that is generated should be
between 600 and 950 mbar (depending on engine size). |
| If the measured value is not reached even through the
preconditions (see notes) have been met, the vacuum system must
first be checked for leaks. |
| – |
For comparison purposes, generate the vacuum with the manual
vacuum pump -VAS 6213-
→ Chapter. |
| Open cut-off valve -B- to
facilitate removal of hose connections and adapter. |
|
|
|
Special tools and workshop equipment
required
Vacuum gauge for brake servo -VAS 6721-
...
Note
The average air pressure of the earth's atmosphere at sea
level is 1013 mbar and decreases steeply as the altitude
increases (approx. 100 mb ...
Other materials:
Steering rack
To achieve the desired results when performing repairs on
the steering rack it is important to work with the greatest
possible care and cleanliness, and to use proper tools in good
condition. Also note the basic rules on safety when performing
repair pro ...
Structure of factory finish, base coat
Base coat, 2-door
-
Base coat
Only the coloured areas of the body receive a base coat.
Base coat, 4-door
-
Base coat
Only the co ...
Removing and installing mounting bracket, LHD vehicles
Remove dash panel end cover on driver side
→ General body repairs, interior; Rep. gr.70.
–
Remove footwell cover on driver side
→ General body repairs, interior; Rep. gr.68.
â ...
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Connecting vacuum gauge for brake servo -VAS 6721-
Checking for leaks