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Home >> Acura >> 1994 >> Integra (GS-R) L4-1797cc 1.8L DOHC (VTEC) >> Repair and Diagnosis >> Powertrain Management >> Emission Control Systems >> Evaporative Emissions System >> Evaporative Check Valve >> Testing and Inspection >> Two-Way Valve Testing
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Two-Way Valve Testing

1. Remove the fuel fill cap.
2. Remove vapor line from the two way valve on the fuel tank and connect to T-fitting from vacuum gauge and vacuum pump as shown.

EVAP Two-way Valve System Testing (1 Of 2):






3. Apply vacuum slowly and continuously while watching the gauge.


^ Vacuum should stabilize momentarily at 5-15 mm.Hg (0.2-0.6 in.Hg)

^ If vacuum stabilizes (valve opens) below 5 mm.Hg (0.2 in.Hg) or above 15 mm.Hg (0.6 in.Hg), install a new valve and retest.


4. Move vacuum pump hose from vacuum to pressure fitting, and move vacuum gauge hose from vacuum to pressure side as shown.

EVAP Two-way Valve System Testing (2 Of 2):






5. Slowly pressurize the valve watching the gauge.


^ Pressure should stabilize at 10-35 mm.Hg (0.4-1.4 in.Hg).

^ If pressure momentarily stabilizes (valve opens) at 10-35 mm.Hg (0.4-1.4 in.Hg), the valve is OK.

^ If pressure stabilizes below 10 mm.Hg (0.4 in.Hg) or above 35 mm.Hg (1.4 in.Hg), install a new valve and retest.
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