Fast Idle Operation

Engine and throttle body must be at temperature of 77°F (25°C) prior to checking. Check that matching mark on fast idle cam is aligned with center of cam roller. See Fig 1 .
If alignment of marks is required, rotate cam adjusting screw until alignment is obtained. Once correct mark alignment is obtained, check clearance between primary throttle valve and throttle bore wall. Clearance should be .016-.020" (.41-.51 mm). Adjust clearance with fast idle adjusting screw.

Fig 1: Checking Fast Idle Cam

Courtesy of MAZDA MOTORS CORP.