Small Leak. Permanent Fault

Special Tools:
^ 999 5646

Safety
- See Safety instructions for handling fuel.
- Proceed to: Checking Cables And Terminals section below.

Checking Cables And Terminals
- Check that the fuel tank filler cap is on properly and that its seal is intact.
- Check EVAP canister, roll-over valve, EVAP canister shut-off valve and fuel tank hoses and hose connectors.
- Were any faults detected?

Yes:
^ Remedy faults.
^ Proceed to: Verification section below.

No:
^ Proceed to: Checking Fuel Tank Pressure Sensor section below.

Checking Fuel Tank Pressure Sensor
- Start the engine and idle it.
- Go into scrolling values.
- Read off fuel tank pressure and canister purge (CP) valve values. When the canister purge valve opens fuel tank pressure should drop.
- Does the fuel tank pressure drop?

Yes:
^ Proceed to: Test Pressurization Of The Fuel Tank System section below.

No:
^ Proceed to: Checking Fuel Tank Pressure Sensor Hose section below.









Test Pressurization Of The Fuel Tank System
- Max 50 liters of fuel in the fuel tank.
- Ignition OFF.
- Remove EVAP canister shut-off valve from its bracket.
- Clamp hose between canister purge valve and intake manifold with a hose clip to seal it off.
- Carefully disconnect the EVAP canister hose from the canister purge valve.
- Connect tool 999 5646 and 999 5544 to EVAP canister.
- 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.
- Close the cock (pressure may drop to 1-2 kPa (0.15-0.3 psi) before stabilizing) and read off pressure.
- EVAP canister shut-off valve cock
- Wait for 10 minutes.

WARNING: Never leave the car unattended with its system pressurized.

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

Yes:
^ Proceed to: Checking Hose To EVAP Canister Shut-off Valve section below.

No:
^ Proceed to: Checking Fuel Tank System section below.

Checking Hose To EVAP Canister Shut-off Valve
- Check hose to EVAP canister shut-off valve for airtightness and check connectors.
- Are the hose and its connectors OK?

Yes:
^ Proceed to: Checking Fuel Tank Pressure Sensor Hose section below.

No:
^ Proceed to: Checking Fuel Tank System section below.





Checking Fuel Tank Pressure Sensor Hose
- Ignition OFF.
- Remove 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:
^ Remedy or replace hose or nipple.
^ Proceed to: Verification section below.

No:
^ Try a new fuel tank pressure sensor.
^ Proceed to: 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.)

WARNING: Max 10 kPa (1.4 psi).

- Check fuel tank system by spraying it with soapy water from the EVAP canister to the canister purge valve and on the line with the roll-over valve to the fuel tank. 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.

WARNING: Never leave the car unattended with its system pressurized.

- Proceed to: Verification section below.









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

- Ignition OFF.
- Reinstall all hoses/components.
- Ignition ON.
- Disconnect the Volvo Scan Tool (ST) from the VIDA station and use it in stand-alone mode.
- 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 the Diagnostic Test Mode (DTM) menu. Activate leak diagnostic.
- Wait until the diagnostic is complete. This can take up to 2 minutes.

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 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.





- Volvo Scan Tool connect to VIDA station.
- Engine idling.
- Select Volvo Scan Tool to read off diagnostic trouble codes.
- Does the diagnostic trouble code recur?

Yes:
^ Fault not found.

No:
^ Fault corrected.