Throttle Positioner

Warm engine to normal operating temperature. Check and adjust idle speed if required.
NOTE: Turn off air conditioning while adjusting throttle positioner.
Allow engine to idle and note that throttle positioner diaphragm releases throttle blade.
On Corolla models, disconnect vacuum hose from throttle positioner diaphragm. Throttle positioner should now be set.
On Celica, Corona and Pickup models, connect vacuum hose going to throttle positioner directly to intake manifold vacuum. Throttle positioner should now be activated.
On all models, with throttle positioner activated, check engine speed. Engine speed should be as specified in "Throttle Positioner Set Speed" table.
If speed is not as specified, correct by turning the throttle positioner adjusting screw. Reconnect vacuum hose and see that engine returns to idle (within 1-3 seconds on Corolla models).

Throttle Positioner Set Speed