Diesel trucks and cars are tough, but they’re a little more sensitive to cold weather than gas engines. October is the right time to get them ready, while the days are still mild and before the first hard freeze catches you off guard.
Diesel engines don’t use spark plugs. They rely on heat from compressing air to ignite the fuel. On a cold morning, that’s harder to do, so most diesels use glow plugs or a grid heater to warm things up before starting. If one or more of those parts has failed, the engine may crank for a long time, start rough or blow white smoke. Fall is a good time to test them.
Fuel is the next thing to think about. Diesel fuel can thicken and turn cloudy in very cold weather, which can clog the fuel filter and keep the engine from running. Stations in our area switch to a winter blend as temperatures drop, and a fresh fuel filter helps the engine handle any thickening that does happen. If your filter has been in for a while, replace it before winter.
Your batteries matter even more on a diesel. Many diesel trucks have two batteries because it takes a lot of power to crank the engine over in the cold. A weak battery that gets by in October may not make it through the first cold snap.
Many newer diesels also use diesel exhaust fluid, often called DEF, to help clean the exhaust. Keep the tank topped off and buy it from a place with good turnover, since old DEF doesn’t work as well.
Finally, check your coolant protection and your engine block heater, if your truck has one. A heater that plugs in overnight makes cold starts much easier on the engine.
Whether you drive a diesel pickup, a work truck or a European diesel car, we’d be glad to get it ready for the season. Call Home Town Auto Care at (615) 656-8461 or stop by 108 Confederate Dr in Franklin, Monday through Friday from 7 to 5.
