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Test Point 8 - Idle Positioner

TEST POINT 8 - DME 944

Idle Positioner




There is no simple method of testing the idle positioner.

Brief Test: Engine Idle Speed (840 rpm)

A) Screw in throttle bypass screw completely when engine is running at steady idle speed.
After brief deviation the idle speed must return to about 840 rpm.

B) Connect a new idle positioner on the wire plug to check activation of idle positioner from the control unit.
Idle positioner must vibrate noticably (frequency activation) with the engine running.
If engine speed is boosted with the bypass screw, the idle positioner must move in closing direction.
Idle positioner must turn in opening direction when engine speed drops.