Is an engine idle speed of 700 to 800 RPM appropriate?

[KayleeLynn]

An engine idle speed of 700 to 800 RPM is appropriate, as the normal range is 700-800 RPM. If the speed is too low, the engine may vibrate excessively, while a higher speed increases fuel consumption. As long as there is no vibration, design engineers generally aim for the lowest possible idle speed to save fuel. The idle speed may automatically increase by 50-150 RPM under the following conditions: Cold start when the engine coolant temperature is low; battery is low on charge; air conditioning is turned on for cooling. Hazards of unstable idle speed: If the idle speed is too high, check for loose or leaking intake manifold, as it will significantly increase fuel costs and accelerate carbon buildup in the engine. If the idle speed is too low, there is a risk of stalling while driving. If the idle speed fluctuates, it may indicate issues with spark plugs or ignition coils, causing the engine pistons to malfunction and leading to severe vibrations.