To properly adjust the ignition, you need to have a diagnostic scope with a speed meter and a strobe lamp.
1. Connect the diagnostic scope according to the service manual.
2. Start the engine and check if the idle speed matches the value in the table for the engine type. If the engine speed is different, it must be adjusted.
3. Turn the rotary knob on the strobe lamp to set the ignition timing angle on the diagnostic scope measuring section to the value specified in the table.
4. Remove the plug from the clutch housing and illuminate the hole with a strobe lamp. If the TDC setting marks are not opposite each other (see photo 1.83) it is necessary to loosen the bolt securing the ignition distributor housing and turn the distributor at such an angle that the marks on the flywheel and clutch housing coincide. In this position, tighten the bolt securing the ignition distributor housing.
5. Turn off the ignition and disconnect the diagnostic scope.
[The original text is available on the portal VWManual.ru]

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