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Two-Way Valve Test

  1. Remove the fuel filler cap.
  2. Remove vapor line from the fuel tank and connect to "T" fitting from vacuum gauge and vacuum pump as shown. See Fig 4 .
  3. Apply vacuum slowly and continuously while watching the gauge.
  4. Vacuum should stabilize momentarily at 0.2-0.6 in. Hg (5-15 mm Hg).
  5. If vacuum stabilizes and the valve opens below 0.2 in. Hg (5 mm Hg) or above 0.6 in. Hg (15 mm Hg), install new valve and retest.
  6. Move vacuum pump hose from vacuum to pressure fitting, and move vacuum gauge hose from vacuum to pressure side as shown. See .Fig 5
  7. Slowly pressurize the vapor line while watching the gauge.
  8. Pressure should stabilize at 0.4-1.4 in. Hg (10-35 mm Hg).
  9. If pressure momentarily stabilizes and the valve opens at 0.4-1.4 in. Hg (10-35 mm Hg), the valve is OK.
  10. If pressure stabilizes below 0.4 in. Hg (10 mm Hg) or above 1.4 in. Hg (35 mm Hg), install a new valve and retest.
Fig 1: EEC System Diagnostic Flow Chart (1 Of 3)
G00107135Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 2: EEC System Diagnostic Flow Chart 2 Of 3)
G00107136Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 3: EEC System Diagnostic Flow Chart (3 Of 3)
G00107137Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 4: Installing Vacuum Pressure Gauge
G00107138Courtesy of AMERICAN HONDA MOTOR CO., INC.
Fig 5: Pressurizing Vapor Line
G00107139Courtesy of AMERICAN HONDA MOTOR CO., INC.
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