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Checking for leaks in the evaporative emission system

Checking for leaks in the evaporative emission system

Checking for possible leaks


1. Inspect the pressurizing equipment to make sure there are no leaks and that it is fault-free.


2. Make sure that the filler cap is screwed on tightly.

3. Fit a service port if one is not already fitted on the car, see .


4. Connect the pressurizing equipment J41413 to the service port at the EVAP canister purge valve.

Note

Do not use the pressurizer's filler cap adapter as the filler cap seal will not then be in the correct position.


5. Activate the EVAP shut-off valve with the diagnostics tool.

- Select the ”ACTIVATE” menu.

- Select ”ACTIVATE SHUT-OFF VALVE”.

6. Pressurize the system and perform a leakage test as described in the Kent-Moore instruction manual.


Procedure if leak detected



1. The shut-off valve must still be activated.

2. Detach the line from the purge valve on the intake manifold.

3. Pressurize the system further as described in the Kent-Moore instruction manual.

4. Detect the leak with the Ultrasonic Leak Detector J41416. Start from the line detached from the intake manifold and work through the lines and components in the system. Perform a visual inspection at the same time.

Note

It may be necessary to lower the tank slightly to be able to check for possible leaks in the components on top of the tank.


Note

The ultrasonic leak detector is sensitive to ambient noise such as exhaust extractors, pneumatic machines, air nozzles, leaking pneumatic connections, etc.

The workshop ventilation system can create currents of air that can also affect the equipment.

Everything mentioned above can cause a similar, but incorrect, result/detection as a leaking EVAP system.


5. Adjust the sensitivity of the detector to filter out ambient, in many cases, interfering noise.

Note

Major leaks such as a defective shut-off valve or loose hose are difficult to detect as they do not have the ”right sound” to be detected by the ultrasonic leak detector.

Therefore, it is important to perform a visual inspection and component check of the system if there is a very quiet leak.


6. When the leak has been detected and rectified, check the integrity of the system again.

7. Restore the care to its original state.