Start the engine and warm it up to normal operating temperature. Stop the engine and remove the air filter.
Pic. 2.25. Connecting a voltmeter to check the lean air-fuel ratio valve when coasting: B - connector contact
Disconnect the freewheel air-fuel mixture lean system connector. Connect a voltmeter to the contact «IN» connector and «mass» (pic. 2.25).
Start the engine. Increase the engine speed to 3000 min-1, then quickly release the accelerator pedal and observe the voltmeter readings. At a speed of more than 2100+100 min-1 voltage should not be registered, below this frequency the voltmeter should show a voltage of 12 V. Stop the engine and disconnect the voltmeter.
Pic. 2.26. Battery voltage supply for coasting lean valve test
Check the operation of the lean valve while coasting by applying battery voltage as shown in fig. 2.26. A click should be heard when voltage is applied.
Pic. 2.27. The polarity of connecting the voltmeter to the connector when checking the idle switch of the engine of the air-fuel mixture lean system when coasting and the location of the adjusting screw (1)
Check the idle switch as follows. Start the engine and connect a voltmeter to the connector as shown in fig. 2.27. No voltage should be recorded when the engine is idling. Increase the engine speed and check that the voltmeter reads 12 V above 1200-1300 min-1. If necessary, turn the switch adjusting screw until the correct reading is obtained.
Stop the engine, disconnect the voltmeter and install the air filter.