Honda Prelude 1993 Service Manual page 405

EVAP Two Way Valve Test
1. Remove the fuel fill cap.
2. Remove vapor line lrom the fuel tank and connect
to T-titting lrom vacuum gauge and vacuum pump
as snown.
VACUUM/PRESSURE GAUGE
0-4 in. Hg
07JAZ-0010008
PUMP/
F
T-FITTING
3.
Apply vacuum slowly and continuously while walching
the gauge.
Vacuum should stabilize momentarily at 5 to 1 5 mm
H g ( O . 2 t o 0 . 6 i n . H g ) .
a lf vacuum stabilizes (valve opens) below 5 mm
H s ( 0 . 2 i n . H g ) o r a b o v e l 5 m m H g { o . 6 i n . H g l ,
install a new valve and retest.
Move vacuum pump hose from vacuum to pressure
tifiing, and move vacuum gauge hose from vacuum
to oressure side as shown.
Slowly pressuraze the vapor line while watching the
gauge.
Pressure should stabilize at 1O to 35 mm Hg {O.4
t o 1 . 4 i n . H g ) .
a It pressure momentarily stabilizes (valve opens)
a t 1 O t o 3 5 m m H g ( O . 4 t o 1 . 4 i n . H g ) . t h e v a l v e
i s O K .
a lt pressure stabilizes below 1O mm Hg (O.4 in. Hg)
o r a b o v e 3 5 m m H g ( 1 . 4 i n . H g ) , i n s t a l l a n e w
valve and retest.
VACUUM
GAUGE
A973X-
o4'l -
xxxxx
4 .
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