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Home >> Honda >> 2001 >> Prelude Base, Automatic >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P1457: EVAP System Leak Detected (EVAP Canister System) >> EVAP Canister System Leak Test
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EVAP Canister System Leak Test

  1. Turn ignition off. Connect 2 "T" fittings and vacuum pump to hoses between EVAP canister and EVAP 2-way valve as illustrated. See Fig 1 . Connect fuel tank pressure (FTP) sensor to one "T" fitting and vacuum pump/gauge to second "T" fitting. See Fig 1 . Remove vent hose from EVAP canister vent shut valve and cap open port. See Fig 2 . Turn ignition on and go to next step.
  2. Monitor FTP sensor voltage with a scan tool or use a DVOM to measure voltage between PCM connector "D" (16-pin connector) terminals No. 11 (Green/Black wire) and No. 15 (White/Blue wire). See Figure . Using vacuum pump, slowly apply vacuum every 1-2 seconds until voltage reading drops to about 1.5 volts. Ensure engine coolant temperature is above 95°F (35°C). Monitor voltage for 20 seconds. If voltage does not drop to 1.5 volts and hold for 20 seconds, go to next step. If voltage drops to 1.5 volts and holds for at least 20 seconds, check EVAP canister vent shut valve line and connections.
  3. Turn ignition off. Disconnect On-Board Refueling Vapor Recovery (ORVR) vent line from EVAP canister, and cap open port. See Fig 3 . Turn ignition on. Monitor FTP sensor voltage with a scan tool or use a DVOM to measure voltage between PCM connector "D" (16-pin connector) terminals No. 11 (Green/Black wire) and No. 15 (White/Blue wire). See Figure . Using vacuum pump, slowly apply vacuum every 1-2 seconds until voltage reading drops to about 1.5 volts. Ensure engine coolant temperature is above 95°F (35°C). Monitor voltage for 20 seconds. If voltage does not drop to 1.5 volts and hold for 20 seconds, go to next step. If voltage drops to 1.5 volts and holds for at least 20 seconds, check On-Board Refueling Vapor Recovery (ORVR) vent line and connections.
  4. Turn ignition off. Disconnect purge line hose from canister and plug hose. See Fig 4 . Turn ignition on. Monitor FTP sensor voltage with a scan tool or use a DVOM to measure voltage between PCM connector "A" (32-pin connector) terminals No. 11 (Green/Black wire) and No. 15 (White/Blue wire). See Figure . Using vacuum pump, slowly apply vacuum every 1-2 seconds until voltage reading drops to about 1.5 volts. Ensure engine coolant temperature is above 95°F (35°C). Monitor voltage for 20 seconds. If voltage does not drop to 1.5 volts and hold for 20 seconds, replace EVAP canister. If voltage drops to 1.5 volts and holds for at least 20 seconds, check EVAP canister purge control solenoid valve line and connections. If line and connections are okay, perform 2-way valve test. See EVAP 2-WAY VALVE under EMISSION SYSTEMS & SUB-SYSTEMS in SYSTEM & COMPONENT TESTING article.
Fig 1: Connecting 2 "T" Fittings & Vacuum Pump To Hoses
G99B08964Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 2: Removing Vent Hose From EVAP Control Canister Shut Valve
G99F08961Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 3: Disconnecting Hose From EVAP Control Canister
G99H08962Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 4: Disconnecting Purge Line Hose From Canister
G99J08963Courtesy of AMERICAN HONDA MOTOR CO., INC.