Diagnostic Aids

WARNING: This page is about a different car, the 2010 Chevrolet Cobalt. However, it is still accessible from the selected car via links, so may be relevant.

To help locate intermittent leaks, use the J 41413-200 Evaporative Emissions System Tester (EEST) to introduce smoke into the EVAP system. See Special Tools . Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light. See Special Tools .
To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT . See Special Tools .
A condition may exist where a leak in the EVAP system only exists under a vacuum condition. By using the scan tool Purge/Seal function to create a vacuum, seal the system and observe the FTP parameter for vacuum decay, this type of leak may be detected.
If a small leak is difficult to find, it may be necessary to remove the EVAP components and test them one at a time, using the adapters in the J 41413-300 . See Special Tools .
The turbocharged engine is equipped with a one-way flow check valve that will prevent boost pressure from entering the purge line and the EVAP system. This check valve will also prevent flow from the J 41413-200 from the purge valve into the EVAP system. See Special Tools .