15 thoughts on “Warming Up Your Car”

  1. Jason the moron engineer says so …

    Obviously the guy never lived where it’s actually cold outside.

    We let our cars & trucks warm up:
    1. so that the windows don’t frost over on the INSIDE
    when we start to drive
    2. so that the windows don’t freeze over on the OUTSIDE
    when remaining moisture gets spread by the wipers
    3. so that the seats don’t crack from the cold when we sit down
    4. so the steering wheel doesn’t freeze to our hands
    5. so that the car is actually comfortable to drive
    6. so that the transmission is warmed up enough to shift properly
    7. oil dilution – that’s why we change the oil anyway

    Lots more reasons. This twerp is just another hectoring conservationist.

    1. If you can’t start your car because your door lock is frozen, trying warming the lock up with your tongue. It should only take a minute to melt any ice blocking the tumblers.

      1. He hasn’t looked at varying rates of expansion with temperature of differing materials that engines are built from.

    2. Good luck with that in a modern car. Worked fine with our old V6 Buick, but our Civic literally cannot melt the ice on the windshield from idling when cold (e.g. -20C or below). The only way to melt it is to drive.

      The engine is simply too efficient, and can’t generate enough waste heat. At a stop light, you can literally watch the engine temperature go down as you sit there in cold weather.

      I believe the diesel version of our Forester has an electric heater because it can’t even generate enough heat when driving. The gas version we have has heated seats because the HVAC system won’t even turn the heat on until the engine is warm.

      1. Then there’s something wrong with your heating or cooling system if that happens when you stop. Have you checked the heater core?

        I’ve owned more than a few Hondas, and that’s not normal.

        I’m currently driving a 2000 hatchback, and it takes about the same time heating up at high idle and driving around.

        As Eric pointed out, there are other factors at work. Heck, I let my car idle to warm up because it takes me that long to chip or scrape enough ice off to where I can see enough and won’t kill anyone. Even my automatic transmission shifts easier once it warms up a bit.

        It’s gotten pretty nasty here in SW Ohio. First bad winter (so far) we’ve had in a while; mostly low temperatures, but last week we had snow in the 30s and a drop to single digits. Forget the wiper blades, the bloody lock was frozen! Climbing into the drivers seat of a Civic hatchback from the passenger door is not something someone my age should endeavor. The worst part was the entire lock mechanism was frozen. I couldn’t even open it from the inside.

        Fortunately it thawed enough that by the time I got to work I could leave via the driver’s side. Once it’s warmed up it’s a toasty little sucker inside. Wasn’t sure if that would thaw the lock mechanism inside the door though. :-/

      2. There was a good episode of Car Talk where a girl called in complaining about her brother, who was a Navy nuclear engineer. She was freezing her buns off riding in his Honda Civic and she said that he explained to her that the Civic’s engine was sooo efficient that it didn’t produce enough waste heat to warm the car.

        The brothers laughed hysterically at that, and explained that all gasoline engines are about 25 to 35% efficient, so they mostly produce waste heat. They said to tell her brother to check the engine’s thermostat and the heater blend door. Then they kept laughing.

        1. Most of that heat goes out the exhaust, not into the coolant.

          Diesel engines are only about 40% efficient, so manufacturers wouldn’t be having to put electric heaters into them if that 60% of waste heat was available to warm the car.

          1. thermal energy path (gif)

            In a gasoline engine, 30% of the energy goes into the coolant, 40% into the exhaust, and 25% goes to rotating motion.

            They have to have a big honking radiator behind the grill because if they dumped all the waste heat into the passenger compartment people would have to drive with the windows down in the winter, just so they don’t bake.

            A Civic would have a 1.4 to 1.8 liter engine which should burn 0.85 liters to 1 liter of gasoline per hour at idle. That is about 34 megajoules, and 10 MJ of that goes into the coolant at a rate of 2.77 kW, the same as pair of space heaters drawing 22 Amps.

            Check your thermostat and your heater blend door. ^_^

          2. BTW, my car (a Pontiac Grand Am with I think a 3.4 L engine) would never warm up in the winter. After an hour of hard city driving the passenger compartment would still be below freezing. So I had them replace the motor on the heater blend door.

            Now, even in 15 to 20 F temperatures, after staring it and letting it idle for 20 minutes, it’s like getting into a sauna.

          3. At a stop light, you can literally watch the engine temperature go down as you sit there in cold weather.

            From that I’d say your thermostat is stuck open. Should cost $25 to $35 for a new one.

  2. I use Slick 50 with every oil change, but generally only warm up for about 5 minutes unless it’s reeaallly cold.

  3. Here in Canada, such stupid advice would leave you with a broken transmission and a stranded car in minus 40 weather.

    1. I did a job in a giant poultry freezer with about 400 motors, and the system ran fine until the buildings temperature started to drop as it came on line. Then we started tripping motor overloads all over the place. So we unscrewed a gearbox drain plug and watched the gear oil slowly droop, kind of like silly putty, taking almost a minute to reach the bucket underneath. The gear oil (Mobile synthetic) was rated for use down to -20, but only in continuous diesel applications. In an intermittent use electric motor application it never had a chance to warm up. Its viscosity was somewhere between cold molasses and taffy.

      So they had to dismount 400 or so gearboxes, take them into the maintenance room, and warm them up with kerosene torpedo heaters just to get the gearbox oil to drain out, then replace it with oil that was hardly more viscous than gun oil at room temperature.

      1. In SD my buddy would actually start a campfire under his car in the winter. They had electric freeze plugs that weren’t up to the job!

Comments are closed.