Why “Warming Up” in Colder Months is Bad for Your Engine

Part of many morning routines, it’s not uncommon to find cars idling in driveways as drivers wait inside, allowing time for their car to heat up in the cold winter months. Once practical decades ago, many of today’s drivers still believe that warming up their vehicle is good engine maintenance.

The reality of the situation is that idling your vehicle in cold weather is a myth and actually does your engine more harm than good.

Morning Warming: Myth Busted.

Where did this idling myth originate and why do older generations insist on letting their vehicles “warm up” before driving? The answer to these questions is rooted in some truth.

It’s been proven that cars do have lower fuel economy during colder months as a result of many variables, including more energy to warm the vehicle, increased engine friction, tire pressure variation, etc. Before the 1980s and electric fuel injectors, carburetors were responsible for managing the fuel/air mix for engines and did require idling to heat to a proper operating temperature. Today’s electronic sensors, on the other hand, adjust for low temperatures and distribute the correct fuel and air mixture without needing to “warm up.” In other words, we can consider this age-old, engine maintenance myth, busted.

What Actually Happens When Your Car “Warms Up”

The theory behind idling is that you’re allowing enough time for your engine to heat up to an optimal temperature. For most, this temperature is around 40 degrees. Anything below this temperature will cause your engine to “run rich,” and significantly lower your mileage and fuel economy. In addition to wasted energy, the gasoline-heavy mixture in idling engine combustion chambers could potentially wash away necessary oil and lead to other issues down the road.

The only way to truly warm your engine and ensure all fluids are functioning optimally is to drive your vehicle. Experts recommend driving lightly for the first few minutes before reaching high speeds to avoid unnecessary stress on the engine as it reaches 40°F.

Proper Engine Maintenance

The best way to care for your engine in the winter is to conduct routine maintenance. In the colder months, low temperatures affect oil viscosity and, if dirty, can seriously affect your engine’s performance. We recommend that you check oil levels regularly and schedule oil changes when appropriate. Another way to ensure your engine is running optimally this winter is to check your coolant and ensure your system includes a 50% mixture of antifreeze.

In conclusion, when reviewing your winter car-care checklist, make sure that “warming it up” is left off the list and that you are conducting routine engine maintenance. For all your engine needs in these colder months and eventual warm and sunny days, contact the knowledgeable technicians and employees at Sanel NAPA today.

About Sanel NAPA

Since 1920, Sanel NAPA has been a leading auto parts, heavy-duty truck parts, and body shop supplies distributor with over 42 store locations throughout New Hampshire, Vermont, Maine, and Massachusetts. We deliver quality car parts, heavy-duty truck parts, automotive paint and body supplies, and tools and equipment that are durable, dependable, and long-lasting in order to provide our clientele with the best products and services possible. For more information, call (603) 225-4000 or click to find a store near you.

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