Note: Idle speed, CO content and ignition timing must be checked and adjusted together. The lambda probe remains connected during the check.
Clamp the crankcase ventilation hose "1" on the cylinder head with a screw clamp.
Remove the oil level dipstick. To avoid oil splashing, place a rag under the dipstick guide.
Start the engine and let it idle.
Check the averaging factor, otherwise adjust it with the idle speed adjusting screw.
Acceptable limits: 26-30%; nominal value: 28±1%.
Note: If the required averaging factor value cannot be achieved using the adjusting screw, the cause should be found in the fault table and eliminated.
Check the idle speed to control it. It should be 750-850 rpm.
Check the CO content and control current. The permissible range is 4-16 mA. If the control current differs from the required one, set the control current according to the dashed line of the diagram using the CO adjustment screw. The setting value of the control current depends on the altitude of the area relative to sea level. For example: Altitude "B" is 900 m above sea level, the setting value of the control current "A" is within 8±2 mA.
Control value for CO content: 0.3-1.2% by volume.
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