Checking the idle speed (VW Passat B4)

The engine crankshaft speed at idle is automatically maintained within specified limits (800-900 rpm) rotary knob according to the controller commands.

Idle speed is checked on a warm engine (oil temperature not less than 80°C), with correctly adjusted gaps between spark plug electrodes and set initial ignition timing, with a clean air filter element, with current consumers switched off, including the air conditioner, in the absence of fault codes in the memory device of the controller self-diagnostic system. During the check, the engine cooling system fan should not turn on. On cars with automatic transmission, the selector lever should be moved to the "P" or "N" position.

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