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Home >> Suzuki >> 2002 >> XL-7 Plus >> Repair and Diagnosis >> External Pages >> Different car >> Section 6 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P1441: Evaporative System Flow During Non-Purge >> Diagnostic Procedure
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Diagnostic Procedure

WARNING: This page is about a different car, the 2002 Isuzu Trooper. However, it is still accessible from the selected car via links, so may be relevant.
  1. Perform ON-BOARD DIAGNOSTIC II SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD system check, go to next step.
  2. Turn ignition off. Remove fuel filler cap. Turn ignition on. Using scan tool, observe FUEL TANK PRESSURE parameter. If scan tool display reads 1.51 volts, install fuel filler cap and go to next step. If scan tool display is not as specified, go to DTC P0452: FUEL TANK PRESSURE SENSOR LOW VOLTAGE  or DTC P0453: FUEL TANK PRESSURE SENSOR HIGH VOLTAGE  .
  3. Turn ignition off. Disconnect EVAP purge line from EVAP canister. EVAP canister is attached to frame rail under rear of vehicle. Using scan tool, command EVAP vent solenoid valve On (closed). Apply vacuum to EVAP canister until FUEL TANK PRESSURE parameter on scan tool reads 1.52-1.60 volts. If FUEL TANK PRESSURE reading is maintained as specified, go to next step. If FUEL TANK PRESSURE reading can not be maintained as specified, go to step  6.
  4. Disconnect EVAP pressure/purge cart from EVAP service port. Disconnect vacuum source line at engine for EVAP purge solenoid. Connect a vacuum pump to EVAP canister purge valve vacuum source fitting. Apply 15 in. H2 O vacuum. If scan tool FUEL TANK PRESSURE display reads 1.47-1.51 volts and holds steady, go to step  6. If scan tool reading is not as specified, go to next step.
  5. Replace EVAP purge solenoid valve. Repeat test, beginning in step  2.
  6. Check for leaks, kinked or pinched hoses at EVAP system. Ensure that all hoses are routed correctly. Check for leak from EVAP vent valve, and also ensure that filter located near vent valve is not plugged. If problem is found, repair as necessary. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM. If no problem was found, go to next step.
  7. Start engine. Remove fuel cap. Using scan tool, command EVAP vent valve On (closed) and EVAP purge solenoid Off (zero percent). Reinstall fuel cap. Monitor scan tool FUEL TANK VACUUM parameter while holding engine speed at 2500 RPM. If scan tool display reads 30-40 percent when vent valve is ON, and zero percent when purge solenoid valve is OFF, repair is complete. If scan tool display is not as specified, check for intermittent problem. See DIAGNOSTIC AIDS .
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