Component Test

CAUTION: Do not adjust IAB control valve full-close screw. It is factory preset.

1. Check IAB control valve shaft for binding or sticking.
2. Check valve for smooth movement.

Intake Air Bypass Stopper:

3. With engine OFF, be sure "A" of the IAB control valve is in close contact with stopper.

Intake Air Bypass Full Close Screw:

4. With engine idling, be sure "B" of the IAB control valve is in close contact with the full-close screw.
a. If problem found, clean linkage and shafts with carburetor spray cleaner.

Intake Air Bypass Control System:

b. If problem still exists after cleaning, disassemble the intake manifold and check the IAB valve body assembly.