EVAP Canister System, Checking For Proper Seal

EVAP Canister System, Checking For Proper Seal

Function test
- Select the measured value "Test-ID 1 ($1): 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 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 at idle for at least 15 minutes.

- End diagnosis and switch ignition off.

If a leak is detected:
- Check for proper seal.

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

If malfunction persists:
- Check the connection pipes and hoses between diagnostic pump for fuel system and EVAP canister for proper seal, assembly overview of EVAP canister system.
- 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 locking ring of the fuel delivery unit is tightened or whether the sealing ring is leaking; replace if necessary, fuel delivery unit.
- Repeat function test.

If malfunction persists:
- Remove EVAP canister and check for tears and leaks, replace if necessary, assembly overview of EVAP canister system.
- Check connecting pipes 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), Diagnostic mode 4: Reset/erase diagnostic data. Diagnostic Mode 04 - Erase DTC Memory
- Generate readiness code. Monitors, Trips, Drive Cycles and Readiness Codes