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Home >> Suzuki >> 2006 >> Forenza Base, 4D Wagon, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> Engine Control Systems >> Engine Performance - DTC P0401 - P0507 >> DTC P0446: Evaporative (EVAP) Emission Vent System Performance >> Troubleshooting
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DTC P0446: Evaporative (EVAP) Emission Vent System Performance: Troubleshooting

TROUBLESHOOTING CHART

Step Action Value(s) Yes No
1 Perform an On-Board Diagnostic (OBD II) System Check.
Is the system check complete?
- Go to Step 2 Go to On-Board Diagnostic (OBD II) System Check
2
  1. Turn the ignition switch ON, with the engine OFF.
  2. Install a scan tool.

Is DTC P0452 or P0453 also set?
- Go to applicable DTC table Go to Step 3
3 Command the Evaporative (EVAP) Emission Canister Purge Valve and Vent Solenoid ON and OFF with the scan tool.
Does the Purge Valve and Vent Solenoid click ON and OFF?
- Go to Step 4 -
4
  1. Turn the ignition OFF.
  2. Remove the fuel cap.
  3. Turn the ignition ON, with the engine OFF.

Is the Fuel Tank Pressure at the specified value?
0 in. Hg Go to Step 5 Go to "EVAP CONTROL SYSTEM DIAGNOSIS "
5
NOTE: Before continuing with this diagnosis, zero the EVAP Pressure and Vacuum gauges on the EVAP pressure/purge cart J-41413. Also read the temperature variation instruction card.
  1. Reinstall the fuel cap.
  2. Using the scan tool, command the EVAP Vent Solenoid ON (closed).
  3. Connect the EVAP pressure/purge cart J-41413 to the EVAP service port.
  4. Pressurize the EVAP system to the first specified value using the EVAP pressure/purge cart J-41413 (monitor the pressure using the gauge an the cart with the switch in the HOLD position).
  5. Observe the Fuel Tank Pressure on the scan tool.
Is the Fuel Tank Pressure at the second specified value?
1.24 kPa (0.37 in. Hg) Go to Step 6 Go to "EVAP CONTROL SYSTEM DIAGNOSIS "
6
  1. Maintain the first specified EVAP pressure.
  2. Using the scan tool, command the EVAP Vent Solenoid OFF (open) while observing the EVAP pressure gauge on the cart J-41413.

Does the EVAP pressure return to the second specified value within 5 seconds?
1.24 kPa (0.37 in. Hg) Go to Diagnostic Aids Go to Step 7
7
  1. Disconnect the large vent hose from the EVAP canister.
  2. Switch the rotary switch on the cart J-41413 to PURGE.
  3. Start the engine and allow the engine to reach operating temperature.
  4. Observe the vacuum gauge for 5 seconds while holding the engine speed at the first specified value.

Is the vacuum displayed less than the second specified value?
102 kPa (30 in. Hg) 2, 500 rpm Go to Step 8 Go to Step 10
8
  1. Inspect the EVAP vent hose between the EVAP canister and the EVAP Vent Solenoid for being kinked, pinched, or otherwise blocked.
  2. If a problem is found, repair as necessary.

Is the repair complete?
- Go to Step 11 Go to Step 9
9
  1. Turn the ignition OFF.
  2. Replace the EVAP Vent Solenoid.

Is the repair complete?
- Go to Step 11 -
10 Replace the EVAP canister.
Is the repair complete?
- Go to Step 11 -
11
  1. Reconnect all the EVAP hardware that was previously disconnected.
  2. Using the scan tool, command the EVAP Vent Solenoid ON (closed).
  3. Pressurize the EVAP system to the first specified value.
  4. Switch the rotary switch on the cart J-41413 to HOLD.
  5. Using the scan tool, command the EVAP vent solenoid OFF (open) while observing the EVAP pressure gauge on the cart J-41413.

Does the EVAP pressure return to the second specified value within 5 seconds?
1.24 kPa (0.37 in. Hg) System OK Go to Step 2