Large Leak. Permanent Fault

Checking cables and terminals
Check that the fuel tank filler cap is on properly and that its seal is intact.
Check hoses and hose connectors at the EVAP canister, EVAP canister shut-off valve and fuel tank.

Were any faults detected?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Checking vacuum downstream of the canister purge (CP) valve section below.


Remedy faults.
Then continue with:
^ Proceed to Verification section below.













Checking vacuum downstream of the canister purge (CP) valve
- Start the engine and idle it.
- Disconnect the hose between the canister purge (CP) valve and EVAP canister from the canister purge (CP) valve.
- Go into scrolling values list, read off canister purge (CP) valve value. To see if the valve is active or not.
Check that there is vacuum in the canister purge (CP) valve when the valve is activated.

Is there a vacuum?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Checking vacuum to canister purge (CP) valve section below.












Checking vacuum at EVAP canister
- Ignition off.
- Reinstall hose on canister purge (CP) valve.
- Disconnect hose to canister purge (CP) valve from EVAP canister.
- Start the engine and idle it.
- Read off the canister purge (CP) valve value to determine whether the valve is activated or not.
Check that there is vacuum in the hose when the canister purge (CP) valve is activated.

Is there a vacuum?

Yes:
^ Proceed to Checking EVAP canister section below.

No:
^ Proceed to Checking hose section below.









Checking vacuum to canister purge (CP) valve
- Connect hose between canister purge (CP) valve and EVAP canister to canister purge (CP) valve.
- Start the engine and idle it.
- Disconnect hose between canister purge (CP) valve and intake manifold from the canister purge (CP) valve.
Check that there is a vacuum in the hose.

Is there a vacuum?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Checking hose section below.





Replacing component
Try a new canister purge (CP) valve.

Then continue with:
^ Verification section below.



Checking hose
Check if the hose between the canister purge (CP) valve and intake manifold is blocked. Check the hose connection to the intake manifold.

Then continue with:
Verification section below.



Checking EVAP canister
Check that all EVAP canister inlets and outlets are air tight.

Are all inlets and outlets airtight?

Yes:
^ Proceed to Replacing component section below.

No:
^ Proceed to Checking hose between fuel tank and EVAP canister section below.


Checking hose
Check it the hose between the canister purge (CP) valve and EVAP canister is blocked or trapped.

Then continue with:
^ Verification section below.


Replacing component
Remedy or try a new EVAP canister.

See: Emissions Control Systems / Evaporative Emissions System / Evaporative Emission Control Canister.

Then continue with:
^ Verification section below.


Checking hose between fuel tank and EVAP canister
Check that the hose between the fuel tank and EVAP canister is airtight and is not trapped.

Was a fault detected?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Test pressurization of the fuel tank system section below.


Replacing or repairing component
Remedy or replace hose between fuel tank and EVAP canister.

Then continue with:
^ Verification section below.












Test pressurization of the fuel tank system
- Max 30 liters (7.92 US.gal.) of fuel in the fuel tank.
- Ignition off.
- Connect hose from fuel tank to EVAP canister.
- Clamp hose between EVAP canister shut-off valve and EVAP canister with a hose clip to seal it off.
- Carefully disconnect the EVAP canister hose from the canister purge (CP) valve.
Connect manometer 999 5646 to hose and pressure regulator 999 5544 to manometer.
Set pressure to 7 kPa (1 psi) (manometer on 999 5646). Cock at right angles to the hoses.


Warning: Max 10 kPa (1.4 psi)


Let the pressure build up for 5 minutes.
Shut off the cock (the pressure may drop 1-2 kPa (0.14- 0.18 psi) before stabilizing) and read off pressure. EVAP canister hose cock.
Wait for 10 minutes.


Warning: Never leave the car unattended with its fuel tank system pressurized.


The pressure should be stable (it may rise a little due to fuel evaporation).

Is the pressure stable?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Checking fuel tank system section below.









Checking fuel tank pressure sensor
- Disconnect tool 999 5646.
- Connect EVAP canister hose.
- Remove hose clamp from hose between canister purge (CP) valve and intake manifold.
- Start the engine and idle it.
- Go into the scrolling values list and read off the value of the fuel tank pressure and canister purge (CP) valve.
When the canister purge (CP) valve opens the pressure in the fuel tank should drop.

Is pressure in the fuel tank dropping?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Checking fuel tank pressure senor hose section below.



Checking hose to EVAP canister shut-off valve
Check hose to EVAP canister shut-off valve for airtightness and check connectors.

Is the hose OK?

Yes:
^ Proceed to Replacing component section below.

No:
^ Proceed to Replacing or repairing component section below.






Checking fuel tank pressure sensor hose
- Ignition off.
- Remove fuel tank pressure sensor. See: Fuel Tank Pressure Sensor.
- Remove hose with Y-nipple.
Check that the nipple and hoses are not blocked.

Are the nipple and hoses blocked?

Yes:
^ Proceed to next step below.

No:
^ Proceed to Replacing component section below.


Replacing or repairing component
Remedy or replace hose or nipple.

Then continue with:
^ Verification section below.


Replacing component
Try a new fuel tank pressure sensor. See: Fuel Tank Pressure Sensor.

Then continue with:
^ Verification section below.



Replacing component
Try a new EVAP canister shut-off valve.

Then continue with:
^ Verification section below.



Replacing or repairing component
Remedy or replace hose.

Then continue with:
^ Verification section below.









Checking fuel tank system
- Ignition off.
- Carefully pressurize fuel tank system to 7 kPa (1 psi). Cock at right angles to the hoses.


Note: Max 10 kPa (1.4 psi)


Check fuel tank system by spraying soapy water from the EVAP canister to the canister purge (CP) valve. Spray the line between the fuel tank and EVAP canister shut-off valve. Check filler pipe and fuel tank filler cap. It may be necessary to lower the fuel tank in order to fault-trace hoses and connectors on top of the fuel tank.

Remedy leakage.

Then continue with:
^ Verification section below.











Verification


Hint: After carrying out the repair, check that the fault has been remedied as follows:


- Ignition off.
- Reinstall all hoses/components.
- Erase diagnostic trouble codes (DTCs).
- Run the engine to operating temperature (above 70°C [158°F]).
- Air conditioning (A/C) off.
- Gear selector in P or N.
- Engine idling.
- Go into diagnostic test menu. Select leakage diagnostic.
- Wait until the diagnostic is complete. This can take up to 2 minutes.
Read off diagnostic trouble codes (DTCs).


Note: If the texts START CONDITIONS NOT MET or DIAGNOSTIC INTERRUPTED are displayed the diagnostic cannot be carried out. This can have several causes: for example high fuel evaporation, high canister charge, high tank pressure, fuel trim not active or a diagnostic trouble code (DTC) stored after the diagnostic has been activated. Check that no diagnostic trouble codes (DTCs) are stored, restart the car and try to activate the diagnostic again. Sometimes several attempts will have to be made before the diagnostic is carried out.


Does the diagnostic trouble code (DTC) recur?

Yes:
^ Fault not found

No:
^ Fault corrected