Throttle Positioner: Corolla
- Warm engine to normal operating temperature. If necessary, check and adjust idle speed. Allow engine to idle and note that throttle positioner diaphragm releases throttle blade.
- Disconnect vacuum hose from throttle positioner diaphragm. Throttle positioner should now be set. With throttle positioner activated, engine speed should be 1400 RPM.
- If not, correct by turning throttle positioner adjusting screw. Reconnect vacuum hose and see that engine returns to idle within 1-3 seconds.