1. Start the engine and warm it up to normal operating temperature. Engage the parking brake, shift the manual transmission control lever to neutral. Leave the engine running at idle. Make sure that all electrical consumers (lighting fixtures, heater fan, rear window defroster, etc.) disabled.
2. Using a special tachometer (for diesel engines) check the idle speed by comparing it with the regulations (see Specifications at the beginning of the chapter Current service).
3. Adjustment is made using the adjusting screw after loosening its locknut. When finished, do not forget to tighten the locknut.