Evaporative Emission (EVAP) Canister System, Checking For Proper Seal

Evaporative Emission (EVAP) canister system, checking for proper seal

Function test
- Select measuring value "Test-ID 01: Tank leak test" and check whether specified value is being reached.
- 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 a leak is detected.

Checking Proper Seal

If a small or large leak was recognized during the test of the EVAP canister system, proceed as follows.
- Disconnect connecting hose from Leak detection pump (LDP) for fuel supply system at the EVAP canister and seal it:
- Repeat function test.

If malfunction persists:
- Check connecting pipes and hoses between Leak Detection Pump (LDP) and EVAP canister for proper seal.
- 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 fuel delivery unit flange or sealing ring is leaking; replace if necessary.
- Repeat function test.

If malfunction persists:
- Remove EVAP canister and check for tears and leaks, replace if necessary:
- Check connecting lines and hoses between EVAP canister and fuel flap unit or Evaporative Emission (EVAP) canister purge regulator valve 1 for proper seal.
- 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.