Tools Required
J 41413 EVAP Pressure/Purge
Diagnostic Station
Notice: Use the EVAP Pressure/Purge Diagnostic Station J 41413 in order
to provide a clean, dry, low pressure gas source. Do not substitute any other
pressurized gas source. Damage may result to the EVAP system.
Important: Whenever the EVAP DTC diagnostics lead to a no trouble found or an EVAP
purge valve replacement, proceed with the following EVAP canister diagnostics.
- Remove the EVAP canister
purge valve. Refer to
Evaporative Emission Canister Purge Solenoid Valve Replacement
.
- Lightly tap the EVAP purge valve on a clean work area.
- Look for carbon particles or carbon dust exiting from either of
the vacuum ports.
• | Reinstall the purge valve If no carbon release is evident. Continue
with the published service manual DTC procedures. |
• | Continue with this service procedure if carbon is released from
the purge valve. |
- Remove the EVAP canister from the vehicle. Refer to
Evaporative Emission Canister Replacement
.
- Turn off the main cylinder valve (1) on the J 41413
EVAP pressure/purge diagnostic station.
- Disconnect the black hose (4) that connects the nitrogen
cylinder to the cart J 41413
at the pressure regulator (5) by unscrewing the knurled nut
on the pressure regulator.
- Connect a section of the vacuum hose to the open fitting of the J 41413
pressure regulator (5).
- Connect the other end of the vacuum hose to the engine compartment
EVAP purge pipe.
- Turn on the main nitrogen cylinder valve (1).
- Continue to blow any debris from the purge pipe for 15 seconds.
- Return the J 41413
to its original condition by re-installing the black hose (4)
disconnected in Step 6.
- Replace the EVAP canister purge valve with the new component.
Refer to
Evaporative Emission Canister Purge Solenoid Valve Replacement
.
- Replace the EVAP canister with the new component. Refer to
Evaporative Emission Canister Replacement
.
- Connect the J 41413
to the vehicle EVAP service port.
- Turn the 4 position switch to Purge.
- Idle the engine at a normal operating temperature.
- Open the throttle until the engine speed reaches 2000 RPM.
- Observe the H2O vacuum gauge on the EVAP cart. The vacuum should
read more than 15 in. H2O.
• | Check the vacuum supply to the EVAP purge valve if the vacuum
is less than 15 in. H2O. |
• | Continue with the published service diagnostics if the vacuum
is more than 15 in. H2O. |