FixVault
Home › Acura › 2001 › 3.2CL Base › Repair and Diagnosis › Engine Performance › System › Engine Controls - Self-Diagnostics › Diagnostic Tests › DTC P1457: Evaporative Emission (EVAP) Control System

DTC P1457: Evaporative Emission (EVAP) Control System

  1. Disconnect vacuum hose from EVAP canister purge solenoid valve. Connect vacuum pump to disconnected port EVAP canister purge solenoid valve. Apply vacuum to EVAP canister purge solenoid valve. If EVAP canister purge solenoid valve holds vacuum, go to next step. If EVAP canister purge solenoid valve does not hold vacuum, replace EVAP canister purge solenoid valve. If valve is contaminated with charcoal particles, replace EVAP canister and blow out vacuum hoses.
  2. Connect fused jumper wire between ground and PCM 32-pin harness connector terminal No. 6 (Red/Yellow wire). See WIRING DIAGRAMS article. Repair as necessary. Turn ignition on. Apply vacuum to hose. If valve holds vacuum, go to next step. If valve does not hold vacuum, EVAP purge control solenoid valve is okay. Go to step  5.
  3. Turn ignition off. Disconnect EVAP purge control solenoid valve 2-pin connector. Check continuity between ground and EVAP purge control solenoid valve 2-pin connector terminal (Red/Yellow wire). If continuity is present, go to next step. If continuity is not present, repair open in Red/Yellow wire between EVAP purge control solenoid valve 2-pin harness connector terminal and PCM 32-pin harness connector terminal No. 6. See WIRING DIAGRAMS article.
  4. Turn ignition on. Measure voltage between ground and EVAP purge control solenoid valve 2-pin harness connector terminal (Black/Yellow wire). If battery voltage is present, replace EVAP purge control solenoid valve. If battery voltage is not present, repair open in Black/Yellow wire between EVAP purge control solenoid valve 2-pin harness connector terminal and fuse No. 6 (15-amp) in underdash fuse/relay box.
  5. Disconnect vacuum hose from EVAP 2-way valve. Connect a vacuum pump to disconnected port on EVAP 2-way valve and apply vacuum. Turn ignition on. If valve does not hold vacuum, go to next step. If valve holds vacuum, EVAP by-pass solenoid valve/EVAP 2-way valve is okay. Go to step  8.
  6. Turn ignition off. Disconnect EVAP by-pass solenoid valve 2-pin connector. Check continuity between ground and EVAP by-pass solenoid valve 2-pin connector terminal No. 2 (Orange/White wire) on MDX or (Blue wire) on 3.2CL and 3.2TL. See WIRING DIAGRAMS article. Repair as necessary. If continuity is present, go to next step. If continuity is not present, replace EVAP by-pass solenoid valve and "O" rings.
  7. Disconnect PCM 32-pin harness connector. Check continuity between ground and EVAP by-pass solenoid valve 2-pin harness connector terminal No. 2 (Orange/White wire) on MDX or (Blue wire) on 3.2CL and 3.2TL. If continuity is present, repair short in Orange/White wire on MDX or Blue wire on 3.2CL and 3.2TL between PCM 32-pin harness connector terminal No. 3 and EVAP by-pass solenoid valve 2-pin harness connector terminal No. 2. If continuity is not present, substitute known-good PCM, then recheck. If symptom or indication goes away, replace original PCM.
  8. Disconnect vacuum hose from EVAP control canister vent filter. Connect vacuum pump to disconnected port on EVAP control canister vent valve. Connect fused jumper wire between ground and PCM 32-pin harness connector terminal No. 4 (Light Green/White wire). Turn ignition on. Apply vacuum. If valve does not hold vacuum, go to next step. If valve holds vacuum, EVAP control canister vent shut valve is okay. Go to step  11.
  9. Turn ignition off. Disconnect EVAP control canister vent shut valve 2-pin connector. Check continuity between ground and EVAP control canister vent shut valve 2-pin harness connector terminal No. 2 (Light Green/White wire). If continuity is present, go to next step. If continuity is not present, repair open in Light Green/White wire between PCM 32-pin harness connector terminal No. 4 and EVAP control canister vent shut valve 2-pin harness connector terminal No. 2. See WIRING DIAGRAMS article. Repair as necessary.
  10. Turn ignition on. Measure voltage between ground and EVAP control canister vent shut valve 2-pin connector terminal No. 1 (Black/Yellow wire). If battery voltage is present, replace EVAP control canister vent shut valve and O-ring. If battery voltage is not present, repair open in Black/Yellow wire between EVAP control canister vent shut valve and fuse No. 6 (15-amp) in underdash fuse/relay box.
  11. Turn ignition off. Connect two "T" fittings into vacuum hose from EVAP control canister to EVAP 2-way valve. See Fig 1 or Fig 2 . Connect fuel tank pressure sensor to one "T" fitting, and vacuum pump to other "T" fitting. Remove vent hose from EVAP control canister vent shut valve. Cap port to seal fresh air vent for EVAP control canister. See Fig 2 or Fig 3 . Turn ignition on. Measure voltage between PCM 32-pin harness connector terminal No. 29 (Light Green wire) and PCM 31-pin harness connector terminal No. 18 (Light Green/White wire) on MDX or (Green/Yellow wire) on 3.2CL and 3.2TL while slowly applying vacuum. See WIRING DIAGRAMS article. Continue to pump vacuum until voltage drops to about 1.5 volts. Ensure engine coolant temperature is greater than 95°F (35C°) and vacuum pump has no leak. Check voltage for 20 seconds. If voltage does not drop to 1.5 volts and hold for at least 20 seconds, go to next step. If voltage drops to 1.5 volts and holds for at least 20 seconds, check EVAP control canister vent shut valve line and connections. Repair as necessary.
    Fig 1: Connecting "T" Fittings At EVAP Control Canister
    G99D08413Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Identifying EVAP Canister Vent Shut Valve & 2-Way Valve (MDX)
    G00032265Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 3: Capping EVAP Control Canister Vent Shut Valve Port
    G99F08414Courtesy of AMERICAN HONDA MOTOR CO., INC.
  12. Turn ignition off. Disconnect quick-connect fitting from EVAP control canister. Plug canister port. See Fig 4 or Fig 5 . Turn ignition on. Measure voltage between PCM 32-pin harness connector terminal No. 29 (Light Green wire) and PCM 31-pin harness connector terminal No. 18 (Green/Yellow wire) while slowly pumping vacuum pump. See WIRING DIAGRAMS article. Repair as necessary. Continue to pump vacuum until voltage drops to about 1.5 volts. Ensure engine temperature is greater than 95°F (35°C) and vacuum pump has no leak. Check voltage for 20 seconds. If voltage does not drop to 1.5 volts and hold for at least 20 seconds, go to next step. If voltage drops to 1.5 volts and holds for at least 20 seconds, check ORVR vent line and connections. Repair as necessary.
    Fig 4: Locating EVAP Control Canister Quick-Disconnect Fitting (3.2CL & 3.2TL
    G99I08415Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 5: Identifying EVAP Control Canister Quick-Disconnect Fitting (MDX)
    G00032266Courtesy of AMERICAN HONDA MOTOR CO., INC.
  13. Turn ignition off. Disconnect purge line hose from canister at metal line. Plug disconnected hose. See Fig 2 or Fig 6 . Turn ignition on. Measure voltage between PCM 32-pin harness connector terminal No. 29 (Light Green wire) and PCM 31-pin harness connector terminal No. 18 (Green/Yellow wire) while slowly pumping vacuum pump. Continue to pump vacuum until voltage drops to about 1.5 volts. Ensure engine coolant temperature is greater than 95°F (35C°) and vacuum pump has no leak. Monitor voltage for 20 seconds. If voltage drops to 1.5 volts and holds for at least 20 seconds, check EVAP purge control solenoid valve and connections. Repair as necessary. If EVAP purge control valve and connections are okay, go to next step. If voltage does not drop to 1.5 volts and hold for at least 20 seconds, replace EVAP control canister and retest.
    Fig 6: Locating Purge Line Hose
    G99F08433Courtesy of AMERICAN HONDA MOTOR CO., INC.
  14. Remove fuel filler cap. Remove vapor hose from EVAP 2-way valve. Connect "T" fitting and vacuum pump/gauge to disconnected EVAP 2-way valve hose. See Fig 7 or Fig 8 . Apply vacuum slowly and continuously while observing gauge. If vacuum stabilizes momentarily at .2-.6 in. Hg, go to next step. If vacuum does not stabilize momentarily at less than .2 in. Hg or at greater than .6 in. Hg, replace valve and retest.
    Fig 7: Checking EVAP 2-Way Valve (3.2CL & 3.2TL)
    G99C08436Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 8: Checking EVAP 2-Way Valve (MDX)
    G00032267Courtesy of AMERICAN HONDA MOTOR CO., INC.
  15. Move vacuum pump hose from vacuum fitting to pressure fitting. Move vacuum gauge hose from vacuum side to pressure side. Slowly pressurize vapor line while observing gauge. If pressure stabilizes momentarily at greater than .3 in. Hg, EVAP 2-way valve is okay. If pressure does not stabilize at greater than .3 in. Hg, replace EVAP 2-way valve and retest.
About FixVault