Checking vacuum hoses to non-return valve, solenoid valves N220 and N75, changeover valve N345 and vacuum reservoir — VW

Checking vacuum hoses to non-return valve, solenoid valves
N220
and
N75
, changeover valve
N345
and vacuum reservoir
Test procedure
Pull vacuum hose
1
off at outer connection of
charge pressure control solenoid valve
N75
.
Pull vacuum hose
2
off at outer connection of
exhaust gas recirculation cooler changeover valve
N345
.
Note
Illustration shows
exhaust flap valve
N220
from below.
Detach vacuum hose
arrow
at outer connection of
exhaust flap valve
N220
.
Connect
hand vacuum pump
VAS 6213
to the 3 valves one after the other and then generate a vacuum of 0.6 bar.
Observe pressure gauge of
hand vacuum pump
VAS 6213
for approx. 30 seconds.
Vacuum must not drop.
If vacuum drops:
Replace a leaking valve.
Seal vacuum hoses
1
to
3
with clean bungs from
engine bung set
VAS 6122
.
Pull vacuum hose
1
off connecting piece
2
.
Seal connecting piece
2
with a clean bung from
engine bung set
VAS 6122
.
Pull vacuum hose
1
off T-piece
2
.
Connect
hand vacuum pump
VAS 6213
to removed end of vacuum hose and generate a partial vacuum of 0.6 bar.
Observe pressure gauge of
hand vacuum pump
VAS 6213
for approx. 30 seconds.
Vacuum must not drop.
If vacuum drops:
Locate damage or leaking vacuum hose connection. To do this, pull individual vacuum hoses off from respective connection and check for leak to connected component.
Pull off vacuum hoses
1
and
2
at connector
arrow
and check non-return valve and vacuum hose to
exhaust gas recirculation cooler changeover valve
N345
.
Locate damage or leaking vacuum hose connection.
Renew non-return valve or leaking vacuum hose.
Reconnect all vacuum hoses to valves and to connecting piece
arrow
.
Pull vacuum hose
arrow
off vacuum reservoir. Seal opening of vacuum hose with clean bung from
engine bung set
VAS 6122
.
Connect
hand vacuum pump
VAS 6213
to removed end of vacuum hose
1
and generate a partial vacuum of 0.6 bar.
Observe pressure gauge of
hand vacuum pump
VAS 6213
for approx. 30 seconds.
Vacuum must not drop.
If vacuum drops:
If vacuum hose
1
leaks, renew it.
If pressure does not drop:
Connect
hand vacuum pump
VAS 6213
to vacuum reservoir and generate a partial vacuum of 0.6 bar.
Observe pressure gauge of
hand vacuum pump
VAS 6213
for approx. 30 seconds.
Vacuum must not drop.
If vacuum drops:
If cylinder head cover leaks, renew it
Chapter
.
If pressure does not drop:
Check following vacuum hoses:
Vacuum hose to
regulating flap potentiometer
G584
Chapter
Vacuum hose to vacuum unit on turbocharger
Chapter
Vacuum hose to vacuum unit on exhaust gas recirculation cooler
Chapter
Checking vacuum system for leaks,
“four-wheel drive”
Chapter