FAQ: Should You Let Your Car Warm Up First?
Starting the car and letting it idle before hopping in is a common practice in winter. No one wants to sit and freeze in a cold car when they go to work in the morning, but is letting your car idle the best way to warm it up?
The answer is no.
Modern car’s don’t require time to idle in order to warm the engine up even in cold weather. In fact, instead of letting it sit idle, the best way to warm up your car’s engine is to start out driving gently. When a car is left to idle, it can actually cause more harm than good. According to the Environmental Protection Agency (EPA), letting your vehicle sit for more than 30 seconds while turned on results in unnecessary air pollution, wasted fuel, and can even cause damage to engine components.
Essentially, when a modern car is left to idle it accomplishes nothing other than wasting gas. Last year, the Washington Post reported on the consequences of idling citing an experiment where three cars were left in cold temperatures and driven the same distance. Before being driven, the cars were left to idle for 5 or 10 minutes. The experiment proved that the more time left idling, the more wasted fuel. A 5-minute warm up resulted in a fuel consumption increase by 7 to 14 percent.
So, where did the misconception about car idling begin?
In the 80s and early 90s, when vehicles were built with carburetors, starting the engine and letting it sit before driving was a realistic way to warm up the engine. When cars were still made with carburetors, drivers could let them sit idle to allow the carburetor to get the right mix of air and fuel in the engine. As more and more vehicles were made with electronic fuel injection systems to replace carburetors, the practice became unnecessary and wasteful. Electronic fuel injection uses sensors to apply fuel to the engine in order to get the right mix of air and fuel.
Now, when you’re getting ready in the morning, you don’t have to worry about warming up your vehicle before driving to work. You can enjoy your morning breakfast and coffee instead!