Civic Sedan L4-1493cc 1.5L SOHC (D15B2) TBI (1989)
Fuel Tank Pressure Release Valve: Testing and Inspection
Fig. 54 Vacuum Gauge Installation
Two-Way Valve Test
1.
Remove the fuel filler cap.
2.
Remove the vapor line from the fuel tank and connect to a T-fitting from a vacuum gauge and vacuum pump as shown.
3.
Slowly apply vacuum while watching the gauge.
Vacuum should stabilize momentarily at 5 to 15 mmHg (0.2 to 0.6 in.Hg)
If vacuum stabilizes (valve opens) below 5 mmHg (0.2 in.Hg) or above 15 mmHg (0.6 in.Hg), install a new valve and retest.
4.
Remove the vacuum pump and re-install it so positive pressure can be applied to the hose.
5.
Slowly pressurize the vapor line while watching the gauge.
The pressure should stabilize at 10 to 35 mmHg (0.4 to 1.4 in.Hg).
If the pressure momentarily stabilizes at 10 to 35 mmHg (0.4 to 1.4 in.Hg), the valve is OK.
If the pressure stabilizes below 10 mmHg (0.4 in.Hg) or above 35 mmHg (1.4 in.Hg), install a new valve and retest.