SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSACURA20043.5RLREPAIR AND DIAGNOSISENGINE PERFORMANCESYSTEMENGINE PERFORMANCE SYSTEM SELF-DIAGNOSTICSDIAGNOSTIC TESTSDTC P1456: EVAPORATIVE EMISSION (EVAP) CONTROL SYSTEM LEAKAGE (FUEL TANK SYSTEM) (2004 3.5RL)
2004 Acura 3.5RL

DTC P1456: Evaporative Emission (EVAP) Control System Leakage (Fuel Tank System) (2004 3.5RL)

2004 Acura 3.5RLSECTION DTC P1456: Evaporative Emission (EVAP) Control System Leakage (Fuel Tank System) (2004 3.5RL)
  1. Ensure fuel filler cap is a Gray Honda cap and is tightened at least 3 clicks to properly seal fuel system. If proper filler cap is installed and properly tightened, go to next step. If proper filler cap is not installed, replace or tighten cap.
  2. Check fuel filler cap seal. If fuel filler cap seal is missing or damaged, replace fuel filler cap. If fuel filler cap seal is not missing or damaged, check fuel filler pipe for damage. If fuel filler pipe is damaged, replace fuel filler pipe. If fuel filler pipe is not damaged, fuel filler cap is okay, go to next step.
  3. EVAP Canister Purge Valve Test:  Disconnect vacuum hose from EVAP Canister Purge Valve (EVAP-CPV) and connect vacuum pump and hose to EVAP-CPV. Turn ignition switch ON (II). Apply vacuum to hose. If EVAP-CPV does not hold vacuum, go to next step. If EVAP-CPV holds vacuum, EVAP-CPV is okay, go to step  6 .
  4. Turn ignition switch off. Disconnect EVAP-CPV 2-pin connector. Check continuity between EVAP-CPV 2-pin connector terminal No. 1 (Red/Yellow wire) and body ground. If continuity is present, go to next step. If continuity is not present, replace EVAP-CPV.
  5. Disconnect PCM 26-pin connector A. See Figure . Check continuity between body ground and EVAP-CPV 2-pin connector terminal No. 1 (Red/Yellow wire). If continuity is present, repair short in Red/Yellow wire between PCM 26-pin connector A terminal No. 23 and EVAP-CPV 2-pin connector terminal No. 1. If continuity is not present, substitute a known-good PCM, and recheck. If symptom or indication goes away, replace original PCM.
  6. EVAP By-Pass Solenoid Valve Test:  Disconnect vacuum hose from EVAP 2-way valve and connect vacuum pump to hose. See Figure . Connect fused jumper wire between body ground and PCM 8-pin connector F terminal No. 1 (Pink/Black wire). See Figure . Turn ignition switch ON (II). Apply vacuum to hose. If EVAP 2-way valve holds vacuum, go to next step. If EVAP 2-way valve does not hold vacuum, EVAP By-Pass Solenoid Valve (EVAP-BPSV) and EVAP 2-way valve are okay. Go to step  9 .
  7. Turn ignition switch off. Disconnect EVAP-BPSV 2-pin connector. Check continuity between body ground and EVAP-BPSV 2-pin connector terminal No. 2 (Pink/Black wire). If continuity is present, go to next step. If continuity is not present, repair open in Pink/Black wire between PCM 8-pin connector F terminal No. 1 and EVAP-BPSV connector terminal No. 2.
  8. Turn ignition switch ON (II). Measure voltage between body ground and EVAP-BPSV 2-pin connector terminal No. 1 (Black/Yellow wire). If battery voltage is present, replace EVAP-BPSV and "O" rings. If battery voltage is not present, repair open in Black/Yellow wire between EVAP-BPSV connector terminal No. 1 and No. 20 ECU (PCM) (20-amp) fuse in underdash fuse relay box.
  9. EVAP Canister Vent Shut Valve Test:  Turn ignition switch off. Disconnect vacuum hose from EVAP Canister Vent Shut Valve (EVAP-CVSV) and connect vacuum pump to hose. See Figure . Turn ignition switch ON (II). Apply vacuum to EVAP-CVSV. If valve holds vacuum, go to next step. If valve does not hold vacuum, EVAP-CVSV is okay. Go to step  12 .
  10. Turn ignition switch off. Disconnect EVAP-CVSV 2-pin connector. Check continuity between body ground and EVAP-CVSV 2-pin connector terminal No. 2 (Red/White wire). If continuity is present, go to next step. If continuity is not present, replace EVAP-CVSV and "O" ring.
  11. Disconnect PCM 8-pin connector F. Check continuity between body ground and EVAP-CVSV 2-pin connector terminal No. 2 (Red/White wire). If continuity is present, repair short in Red/White wire between PCM 8-pin connector F terminal No. 5 and EVAP-CVSV 2-pin connector terminal No. 2. If continuity is not present, substitute a known-good PCM, and recheck. If symptom or indication goes away, replace original PCM.
  12. Vacuum Hoses & Connections Test:  Check vacuum hoses and connections for leaks. Check following parts for leaks to atmosphere: If components or hoses leak, repair or replace as necessary. If no leaks are present and components are okay, substitute a known-good PCM, and recheck. If symptom or indication goes away, replace original PCM.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

Shop Manual-Ready ToolsFree Quote CheckQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.