Two-Way Valve
- Remove gas cap and remove fuel vapor hose from fuel tank to the two-way valve. Connect vacuum/pressure pump with gauge to hose and slowly draw vacuum while observing gauge.
- Vacuum should stabilize at .2-.6 in. Hg as two-way valve opens. Reverse pump and gauge connections and slowly pressurize vapor hose. Pressure should re is voltage, check control unit.
- If there is no voltage at power valve control solenoid valve, remove hose from inlet side of check valve and check vacuum. If there is vacuum, test check valve operation. If check valve tests OK, replace power valve solenoid control valve and retest. If there is no vacuum, check connecting hoses for leaks and obstructions.
- With vacuum gauge connected to hose removed from power valve, ground Red wire of control unit and check that vacuum drops to zero. If vacuum drops, system is OK. If vacuum does not drop, check voltage at power valve control solenoid in control box. See Fig 1 . Connect negative lead of voltmeter to ground and connect positive lead to Green/Blue wire at control box connector.
- If there is no voltage, check control unit. If there is voltage, replace power valve control solenoid valve and retest.