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. |