hours
Conditions for Setting the DTC
* The ECM detects a leak in the EVAP system that is greater than a calibrated amount.
* The ECM must complete several EONV tests before the diagnostic can turn the MIL on or off.
Action Taken When the DTC Sets
DTC P0442 is a Type A DTC.
Conditions for Clearing the DTC
DTC P0442 is a Type A DTC.
Diagnostic Aids
* The EVAP system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is
injected. When injecting smoke at the service port remove the fuel fill cap, or temporarily leave the vent open, until smoke is observed then
close the system and continue testing. If using a fuel cap adapter at the filler neck, use the J 41413-VLV at the service port to allow the
system to fill faster.
* To help locate intermittent leaks using the J 41413-200, move all EVAP components while observing smoke with the J 41413-SPT.
* Individual components can be isolated and tested using adapters in the J 41413-300.
* A condition may exist where a leak in the EVAP system only exists under a vacuum condition. This type of leak may be detected by using
the scan tool Purge/Seal function to create a vacuum in the EVAP system and then observe the FTP parameter for vacuum decay.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Description and Operation
Evaporative Emission Control System Description (See: Powertrain Management/Computers and Control Systems/Description and
Operation/Evaporative Emission Control System Description)
Scan Tool Reference
Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information
Special Tools
* CH-48096 EVAP Service Access Port Tool
* J 41413-200 Evaporative Emissions System Tester (EEST)
* J 41413-300 EVAP Cap and Plug Kit
* J 41413-SPT High Intensity White Light
* J 41413-VLV EVAP Service Port Vent Tool
Circuit/System Testing
Note:
* Refer to the J 41413-200 operation manual for detailed instructions in Evaporative Emission System Diagnosis (See: Powertrain
Management/Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics/Evaporative Emission
System Diagnosis).
* Larger volume fuel tanks and/or those with lower fuel levels may require several minutes for the floating indicator to stabilize.
* The fuel level should be between 1/4 and 3/4 of a tank.
* Ensure that the underbody temperature of the vehicle and the tester are similar.
1. Do not disturb any of the fuel system components after verification of a DTC P0442 on a vehicle.
2. Using a scan tool, close the EVAP canister vent valve to seal the EVAP system.
3. Change the tank pressure sensor units from in H2O to mm Hg for better resolution.
4. Start the vehicle and monitor the tank pressure sensor output value for approximately two minutes.
5. If the tank pressure sensor value DOES change (shows vacuum):
1. Remove the purge solenoid from the vehicle.
2. Pressurize the fuel tank side of the purge solenoid with J 41413-200.
3. Add smoke and allow pressure to stabilize for 2 minutes.
4. If smoke is allowed to pass through the purge solenoid, replace the purge solenoid.
6. If the tank pressure sensor value DOES NOT change:
1. Install CH-48096 adapter between the purge line from the canister and the purge solenoid. Do not use any other adapter or pressurization
