Fuel AUDI A4 1999 B5 / 1.G EVAP User Guide

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Installing
Installation is in reverse order of removal, but do
the following:

Note:
Secure all hoses with clamps that are the same
as factory installed.

CAUTION!

Always refer to the latest parts catalog to
ensure that you use original equipment fuel
hose clamps.

Tightening torque: - Secure hose -2- with tie wrap -1- to bracket of LDP.Component
Nm
Bracket for Leak Detection Pump (LDP) 7.5
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EVAP canister, removing and installing


Note:
To check seal integrity, perform tank leak
diagnosis Page 20
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Removing

- Remove cover for EVAP canister at bottom of
spare tire well.

Installing
Installation is performed in the reverse order of the removal procedure,
during installation note the following:
CAUTION!
Always refer to the latest parts catalog to ensure that you use
original equipment fuel hose clamps. - Loosen hose connections -1- and - 3- on bleed lines.
- Remove sealing pieces out and over the bleed lines.
- Loosen studs -arrows-.
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If vehicle fails above test ("System not OK"):

- Verify fuel cap is properly closed; repeat test.
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If "System OK" after re-test:

- Erase DTC memory (if necessary).

- Repeat test several times to ensure proper
EVAP system operation (remove and re-install
fuel cap before each test).

- Perform quality check and return vehicle to
customer.

Note:
If the vehicle passes the above EVAP system
test, DTCs may be sporadic; the entire EVAP
system should be carefully inspected.
If VAS 5051 continues to indicate "System not
OK" after re-test, proceed to next step.

Perform EVAP tester self-test

Note:

Always perform system self-test of KLI9210
EVAP Tester prior to use to ensure that there
are no leaks.
Refer to KLI9210 instruction manual for specific
instructions.
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Note:
If the leak cannot be located or repaired, contact
K-Line Customer Service - Technical Support.

Calibrate KLI9210 Tester
Determine vehicle leak threshold:

To m.y. 2000: leak threshold 0.040 in.

From m.y. 2001: leak threshold 0.020 in.

Test fuel cap - Attach test hose to appropriate preset port (black arrows).
- Turn control valve from "Hold" to "Test".
- Set flow meter flag (white arrow) at indicated value on flow meter.
- Turn control valve to "Hold"; remove test hose.
- Connect fuel cap tester to hose.

If no flow is indicated: - Screw fuel cap tightly to cap receiver (arrow).
- Turn control valve to "Test".
- Read flow meter on tester.
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If flow is indicated:

- Replace fuel cap and re-test.
If new fuel cap shows no flow:

- Repeat Leak Test, with new fuel cap installed,
using VAS 5051 and Basic Settings mode,
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If Leak Test shows 'System OK":

- Perform quality check and return vehicle to
customer.

Test LDP -V144- for internal leaks
If vehicle is not LDP-equipped, proceed to "Test
EVAP system".

- Clamp off LDP outlet (EVAP side) using Special
Tool No. 3094 or equivalent.

CAUTION!

Clamp only soft rubber lines when isolating a
leak. To avoid risk of damage, never clamp
hard plastic lines!

-
Repeat Leak Test using VAS 5051 and Basic
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Note:
Fuel system pressurization depends on volume of fuel system and
amount of fuel in tank.
If fuel system pressurization does not stabilize:
CAUTION!
Clamp only soft rubber lines when isolating a leak. To avoid risk of
damage, never clamp hard plastic lines!
Note:
Any flow shown on flow meter indicates a leak. Flow before flow meter
flag set at vehicle leak standard may indicate a sporadic DTC.
If flow meter on tester registers flow near or above preset pressure: - Attach fuel cap adapter to filler neck (arrow) and test hose to adapter.
- Turn control valve from "Hold" to "Test".
- Allow fuel system to pressurize.
- Verify all fuel system outlets have been sealed before continuing.

- Clamp off hose (arrow) leading from EVAP purge regulator valve -N80-
to intake manifold (pictured: AHA engine in A6).
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If flow stops:

- Replace EVAP purge regulator valve -N80- and
repeat test before continuing.
If meter indicates no flow after test:

- Perform a quality check and return vehicle to
customer.
If flow continues, proceed as follows:

Method 1: Locate leak with smoke generator

- Connect leads from smoke generator to vehicle
battery.

- Use smoke generator trigger to charge fuel
system with smoke.

- Inspect complete EVAP system for escaping
smoke.
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Method 2: Locate leak with ultrasonic tester
If leak cannot be located:
CAUTION!
Clamp only soft rubber lines when isolating a leak. To avoid risk of
damage, never clamp hard plastic lines! General search: tester only
Localized search: tester with extension (on left in illustration)
- Disconnect and plug or clamp shut EVAP lines to isolate fuel tank,
using Special Tool No. 3094 or equivalent, before continuing.
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If flow stops:

- Reconnect EVAP lines to search area that was
isolatedl
If leak or source of fuel odor cannot be found:

- Contact Audi Dealer Technician Helpline.

CAUTION!

Under no circumstances should the vehicle
be returned to the customer without proper
diagnosis and repair.
When leak has been located:

- Repair leak and repeat EVAP system test.

- Perform quality check and return vehicle to
customer.

Note:

Because leak may be at top of fuel tank, it may
not be possible to locate through fuel
pump/sending unit access plate.
Fuel tank may need to be lowered to locate the
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