lock AUDI A6 1995 C5 / 2.G AEB Engine EVAP System Checking

24-139

Evaporative Emission (EVAP) Canister
Purge Regulator Valve, checking


Required special tools and test equipment

VAG 1551 or VAG 1552 Scan Tool (ST) with
VAG 1551/3 adapter cable

Test conditions
Engine coolant temperature at least 80 C
(176 F)

Function check

- Connect VAG 1551 or VAG 1552 scan tool and
press buttons -0- and -1- to insert "Engine
Electronics" address word 01 (with engine
running at idle) Page 01
-7 .
Rapid data transfer
HELP
Selectin
g function XX

Indicated on display
- Press buttons -0- and -8- to select "Read Measuring Value Block"
function 08, and press -Q- button to confirm input.
Read Measurin
g Value Block
HELP
Input displa
y group number XXX

Indicated on display
- Press buttons -0-, -7- and -0- to input display group number 70, and
press -Q- button to confirm input.
Pa
ge 4 of 12 Eva
porative Emissions
(EVAP
) system, checkin
g
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.24.4

Read Measuring Value Block 70 1 2 3 4

Indicated on display (1-4 = display fields)
Pa
ge 5 of 12 Eva
porative Emissions
(EVAP
) system, checkin
g
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.24.4

24-141


Display fields

1 2 3 4
Display group 70: EVAP canister purge regulator valve
Display xxx % xx.x % xx.xx g/s Test OFF/Test
ON
EVAP OK
EVAP notOK
Indicated EVAP canister purge regulator
valve duty cycle during diagnosis Oxygen sensor deviation
during diagnosis Idle Air Control (IAC) valve
deviation during diagnosis Diagnosis
condition
Diagnosis
results
Range 0-100 % -25.0 to 25.0 % -2.70 to 4.16 g/s ---
Specified
value 0-100 % - 5.4 to 9.4 % 0.00-0.33 g/s EVAP OK If "EVAP notOK" is indicated in display field 4:

- Check for blockage or leaks Page 24
-142
.
If "EVAP OK" is indicated in display field 4:

-
Press button to advance program
sequence.
Pa
ge 7 of 12 Eva
porative Emissions
(EVAP
) system, checkin
g
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.24.4

24-142

Checking for blockage and leaks
The EVAP canister purge regulator valve is
closed when power is off.

- Remove EVAP canister purge regulator valve -
N80- (component locations Page 24
-1 )

- Connect removed valve to harness connector.

- Start output Diagnostic Test Mode (DTM) and
select -N80- Page 01
-42
.

- Blow into long connection during output DTM,
and check whether valve opens and closes
properly. Replace valve if necessary.

- If valve is OK, check all hose connections
between tank and valve for blockage or leaks.

EVAP canister purge regulator valve -N80-
electrical test

- Disconnect harness connector from EVAP
canister purge regulator valve.

- Connect multimeter US 1119 (Fluke 83 or equivalent) and check
resistance at across valve terminals.
Pa
ge 9 of 12 Eva
porative Emissions
(EVAP
) system, checkin
g
11/19/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU02.24.4