Idle mixture quality adjustment screw

The mixture quality adjustment screw is shown by the arrow.
Idle speed is controlled by the ESC II electronic module.
To adjust the quality of the mixture, you need to have a tachometer and an exhaust gas analyzer.
1. Check the condition of the air filter and replace if necessary.
2. Warm up the engine to operating temperature.
3. Turn off all electrical consumers.
4. Check the initial ignition timing setting.
5. Connect a tachometer (with the ignition off) and a gas analyzer to the engine.
6. Increase engine speed to 3000 rpm and hold it for 30 seconds, then return the engine to idle.
7. Take instrument readings.
8. If the CO content value deviates, remove the protective cap from the mixture quality screw, increase the engine speed to 3000 rpm and hold it for 30 seconds, then switch the engine to idle mode and, by turning the mixture quality screw, set the required CO level.
Attention! Readings of the instruments and adjustments can be made only after the readings of the measuring instruments have stabilized.
(A copy of the article is available on the website fordbook)