ignition AUDI A4 1998 B5 / 1.G EVAP User Guide

20-159
If you did not find any malfunction, however the
Leak Detection Pump (LDP) did not function
during the Output Diagnostic Test Mode (DTM):

- Replace LDP Page 20
-162
If the LED does not blink, although wiring is OK:

- Replace the Engine Control Module (ECM)

Repair Manual, Fuel Injection & Ignition,
Repair Group 24
- Generate readiness code:

Repair Manual, Fuel Injection & Ignition,
Repair Group 24
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20-160

Checking input wiring (vehicles with
mechanical throttle activator)

- Switch ignition off.

- Connect test box VAG1598/22 to harness connector Page 20
-153
,
"Checking output wiring."

Repair Manual, Fuel Injection & Ignition, Repair Group 24 - Check the following wire connections for open circuit or short circuit to
Ground or plus (B+): Electrical connector terminal
Test box VAG1598/22 socket
2 37
- Repair open or short circuit as necessary.
- Generate readiness code:
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20-161

Checking input wiring (vehicles with
electronic throttle control)

- Switch ignition off.

- Connect test box VAG1598/31 to harness connector Page 20
-156
,
"Check output wiring."

Repair Manual, Fuel Injection & Ignition, Repair Group 24 - Check the following wire connections for open circuit or short circuit to
Ground or plus (B+): Electrical connector terminal
Test box VAG1598/31 socket
1 80
- Repair open or short circuit as necessary.
- Generate readiness code:
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20-162

Leak Detection Pump (LDP) -V144,
removing and installing

Checking LDP Page 20
-139


Removing

- Remove left rear wheel.

- Remove left rear wheel housing liner.

Repair Manual, Body Exterior, Repair Group
66


- Cut tie wrap -1- and remove hose -2- .
- Disconnect hose coupling -3- after pressing tab.
- Remove nuts -arrows-.
- Switch off ignition.
- Remove LDP, unclip and disconnect connector.
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20-176


EVAP system leak detection circuit,
schematic diagram (vehicles with 1.8 ltr.
turbo engine)

Repair Manual, 1.8 Liter 4-Cyl. 5V Turbo Fuel
Injection & Ignition, Repair Group 24 1 -
Check valve
Location (light/dark side): as shown in
illustration
2 -
EVAP canister purge regulator valve -N80-Location: in engine compartmentChecking
3 -
Bleed line
From EVAP canister purge regulator valve
-N80-
LocationRight side under floor panFront-wheel drive: on floor pan in area of
fuel tank All-wheel drive: on fuel tank in area of fuel
tank
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20-180


EVAP system leak detection circuit,
schematic diagram (vehicles with 2.8 ltr.
engine)

Repair Manual, 2.8 Liter V6 5V Fuel Injection &
Ignition, Repair Group 24 1 -
Throttle actuator control module -J338-
2 -
EVAP canister purge regulator valve -N80-Location: in engine compartmentChecking:
3 -
Bleed line
From EVAP canister to EVAP canister
purge regulator valve -N80-
LocationOn right side under floor panVehicles with front-wheel drive: mounted
on floor pan in area of fuel tank Vehicles with all-wheel drive: mounted on
fuel tank
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20-183


EVAP system leak detection circuit,
schematic diagram (vehicles with 2.7 ltr.
turbo engine)

Repair Manual, 2.7 Liter V6 5V BiTurbo Fuel
Injection & Ignition, Engine Code(s): APB, Repair Group 24
1 -
To air intake before both turbo chargers
2 -
Check valve Installation position: Arrow at housing
indicates flow-through direction.
3 -
Evaporative Emission (EVAP) canister
purge regulator valve -N80- Location: On right side of engine
compartment Checking:
4 -
Vent line
From EVAP canister to EVAP canister
purge valve regulator valve -N80 Installation position: On right side on
vehicle under-side. Attached to fuel tank.
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