With Generic Scan Tool

EVAP Canister System, Checking For Proper Seal


NOTE: For vehicles with engine code AEG, the test for "EVAP canister system, proper seal" is only possible as of model year 99.


Function test
- Select the measuring value "Test-ID 01: Tank leak test" and check whether the specified value is being reached, Diagnostic mode 8: Tank leak test.
- Check specified value of tank leak test at idle. Specified value: Test function active


NOTE:
- During tank leak test, Engine Control Module (ECM) limits "test function active" to 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 at idle.

- End diagnosis and switch ignition off.

If specified value is not obtained:

Checking Proper Seal

If a small or large leak was recognized during the test of the EVAP canister system, proceed as follows.
- Remove rear right wheelhouse liner.
- Disconnect connection hose from diagnostic pump for fuel system at EVAP canister and seal it, item 11.
- Repeat function test.

If malfunction persists:
- Check the connection lines and hoses between diagnostic pump for fuel system and EVAP canister for proper seal, Parts of the EVAP canister system, removing and installing.
- Repeat function test.

If malfunction persists:
- Check whether the fuel filler cap is completely closed or whether the seal leaks, replace if necessary.
- Check whether the union nut of the Fuel Pump (FP) unit is tightened or whether the sealing ring is leaking; replace if necessary, Fuel Pump (FP) unit, removing and installing.
- Repeat function test.

If malfunction persists:
- Remove EVAP canister and check for cracks and leaks, replace if necessary, Parts of the EVAP canister system, removing and installing.
- Check connecting pipes and hoses between EVAP canister and fuel flap unit or Evaporative Emission (EVAP) canister purge regulator valve 1 for proper seal.

Overview plan of EVAP canister system:
- Vehicles with engine code AEG, AVH, AZG.
- Vehicles with engine code BDC.

- Check hoses and hose clamps for secure seating.
- Repeat function test.

If malfunction is no longer present:
- Erase DTC memory of Engine Control Module (ECM).
- Generate readiness code.