Honda Prelude 1993 Service Manual page 386

Intake Air System
Intake Air Bypass (lABl Control System
lExcept F22Al engine {S}l (cont'd}
IAB Valve Testing
CAUTION: Do not adjust the IAB valve full-close 5c1€w.
It was preset 8t the factory.
1. Check the IAB valve shaft for binding or sticking,
2. Check the IAB valve for smooth movement.
3. With the engine OFF, ctreck that @ of the bypass
valve is in close contact with the stoDper.
4.
With the engine at idle, check that (9of the IAB
valve is in close contact with the full-close screw.
a ll sny fautt is found, cl€an the linkago and shafts
with calbuistor clssner.
lf the Droblem still exists after cleaning, disassem-
ble the intake manifold and check the IAB valve
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