Diagnostic Aids
WARNING: This page is about a different variant/trim than selected.
- When using the J 41413-200 Evaporative Emission System Tester (EEST) to apply pressure, you can regulate the amount of pressure by activating the remote switch ON and OFF while observing pressure in the EVAP system using a scan tool. See Special Tools .
- A restriction in the EVAP canister or vent lines could prevent fuel vapor pressure from bleeding off fast enough. If the vent system cannot bleed off pressure fast enough, this code can set. When pressure is applied to the system and released, a properly operating system will return to the atmospheric pressure rapidly. By using a scan tool and the J 41413-200 , pressure can be applied to the system, then released, while monitoring the FTP sensor parameter to see that pressure can be released within 30 seconds. See Special Tools .
- An FTP sensor that is skewed or does not have a linear transition from low to high may cause this code to set. A scan tool output controls, snapshot, and plot functions can help detect erratic sensor response. To test the sensor signal under vacuum conditions, use the Quick Snapshot and the Purge/Seal functions to capture data while commanding purge to 20 percent, then plot the data to look for erratic sensor operation. A similar test can be done for the pressure side of the sensor operation by applying pressure with the J 41413-200 while taking a snapshot. See Special Tools .
- A full fuel tank may cause misdiagnosis.