Brian asks by email: “I have a neighbor who goes outside and starts his truck every morning at 6 a.m. I know this because when the engine starts, his headlights come on and they are pointed right at my bedroom window. The truck runs until he leaves at 6:45, which means that the engine is running all that time. Last year, I talked to him and he said that his father always warmed up the engine before driving it and he has been doing it, too. He even does it in warm weather because he says it sits outside all night and needs to be “woken up” before he drives it. I think it is a waste of gas. Is he right or am I right that today’s vehicles don’t have to be started and allowed to run before driving first thing in the morning.”
You are right, Brian. While no one really likes to get into a cold vehicle, it is a waste of time and fuel to allow the engine to run before driving. Even vehicles that have a remote start feature limit the engine run time to 10 minutes. The best and most efficient way to warm up a vehicle is to start the engine and fasten the seatbelt. By that time, the engine oil pressure has been established and the vehicle is ready to drive. Drive slowly for the first few miles, if possible, before entering a freeway and driving at highway speeds. This procedure also allows the transmission fluid and final drive fluid (differential, if equipped) to warm, whereas your neighbor’s truck has warmed just the engine.