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

Checking vacuum hoses leading to non-return valve, solenoid valves
N220
and
N75
changeover valve
N345
Test procedure
Pull vacuum hose
3
off at outer connection of
exhaust gas flap valve
N220
4
.
Pull vacuum hose
2
off at outer connection of
charge pressure control solenoid valve
N75
1
.
Pull vacuum hose
6
off at outer connection of
changeover valve for exhaust gas recirculation cooler
N345
5
.
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:
Check vacuum hoses for damage, and renew damaged hoses.
Seal vacuum hoses
2, 3 and 6
with clean bungs from
engine bung set
VAS 6122
.
Seal connecting piece
2
with a clean bung from
engine bung set
VAS 6122
.
Pull vacuum hose
1
off cylinder head cover
2
.
Seal opening of vacuum hose with clean bung from
engine bung set
VAS 6122
.
Pull vacuum hose off T-piece
2
.
Connect
hand vacuum pump
VAS 6213
to removed vacuum hose and 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:
Locate damage or leaking vacuum hose connection. To do this, pull individual vacuum hoses off from relevant 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 union
arrow
.
Pull vacuum hose
1
off cylinder head cover
2
.
Seal opening of vacuum hose with clean bung from
engine bung set
VAS 6122
.
Connect
hand vacuum pump
VAS 6213
to removed vacuum hose and 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 vacuum hose if it leaks
1
.
If pressure does not drop:
Connect
hand vacuum pump
VAS 6213
to vacuum reservoir and 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:
Renew cylinder head cover if it leaks.
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