Modern engines function well within 30 seconds of being started. Idling for extended periods of time only wastes fuel and puts unnecessary stress on the engine. This may actually damage the engine, as fuel does not fully combust while idling.
Rather than idling, the car should be "warmed up" by driving slowly and gently at first. The engine will warm up to its optimum operating temperature more effectively while in motion, meaning a car may be driven almost as soon as it is started.
Cars need to be warmed up, but this can be done on the road and after driving only a short distance. Most cars can be driven within 30 seconds of being started, states Consumer Energy Center.
