Diagnostic mode 8: Tank leak test

WARNING: This page does not describe the selected car, but rather 14 other vehicles, including the 2005 Volkswagen GTI, 2004 Volkswagen R32, 2004 Volkswagen Jetta, 2004 Volkswagen GTI, and 2003 Volkswagen Jetta. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: This diagnostic mode can only be selected with Module number 10 - Engine Electronics.

Function

This diagnostic mode checks the fuel system for leaks.

NOTE:

The Evaporative Emission (EVAP) Canister Purge Regulator Valve(s) and Leak Detection Pump (LDP) -V144- seal the tank system.
Pressure (max. 70 mbar) can be applied to the fuel system via the test connection (in engine compartment, right) and via engine leak detection spray (e.g.: G 001 800 A1) leaks can be detected.

Test requirements

There must not be any DTCs stored in DTC memory. Refer to Diagnostic mode 3: Check DTC Memory
Coolant temperature must be 80 to 110 ° C. Refer to Diagnostic mode 1: Check measured values
Intake air temperature must not be above the maximum of 60 ° C. Refer to Diagnostic mode 1: Check measured values

Function test

Connect diagnostic tester. Refer to Diagnostic tester, connecting
Start engine and let run 15 minutes at idle.
Under address word 33, select "Diagnostic mode 8: Tank leak test".
Select measuring value "Test-ID 01: Tank leak test".

Check specified value of tank leak test at idle.

Evaluation test-ID 01: Tank leak test

Tank leak test

Specified value:

Test function:

is being initiated, please wait
aborted

active
off

Test function active

NOTE:

During tank leak test, Engine Control Module (ECM) limits "test function active" to approx. 12 minutes.
If the accelerator pedal is depressed during the test, the test will be aborted.
To repeat the tank leak test, switch ignition off and start engine again and let run 15 minutes at idle.

End diagnosis and switch ignition off.

If a leak is detected:

EVAP canister system, checking for proper seal. Refer to Evaporative Emission (EVAP) canister system, checking for proper seal .
Check Evaporative Emission (EVAP) Canister Purge Regulator Valve -N80-. Refer to Evaporative Emission (EVAP) canister purge regulator valve 1, checking .
Leak Detection Pump (LDP) -V144-, checking. Refer to Leak Detection Pump (LDP), checking .

Vehicles with engine code BJS

Check Evaporative Emission (EVAP) Canister Purge Solenoid Valve -N115-. Refer to Evaporative Emission (EVAP) canister purge solenoid valve 2 (vehicles with engine code BJS), checking .

Continuation for all vehicles

Erase DTC memory of Engine Control Module (ECM). Refer to Diagnostic mode 4: Reset/erase diagnostic data
Generate readiness code. Refer to Readiness code, generating