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With the new technologies in cars today, is it still necessary to allow a car to warm up before driving it?

I heard once that allowing a car with a catalytic converter to warm up is a waste of time and gasoline. Is this true?

7 Answers

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  • 1 decade ago
    Favorite Answer

    Generally speaking, if it's warm weather, I let mine run for about 30 seconds, and go. If it's cold enough for a coat, I let it run for about two minutes.

    This gives the lubrication a few moments to circulate, and begin to warm up. If it's exceptionally cold, I let it run until the air from the heater begins to get warm.

  • Doug K
    Lv 5
    1 decade ago

    A modern fuel injected car is much better when it comes to cold weather since the computer controls the fuel input appropriately. What IS necessary is allowing enough time for the oil to circulate through the engine properly. Most engine oils have a number like 10w-30 or 20w-50. The first number is the engine 'weight' or, to put it in layman's terms, how thick the oil is, when it is cold (specifically 0* F.) As the engine warms up, the oil gets thicker. The second number is the oil's 'weight' when it is warmed up (specifically 212* F.) When the oil is thin, it has less protecting capability for the engine parts, but is easier for the engine to push around inside all the oil passages. Most cars have a 'fast idle' when they are cold. This allows the engine to quickly and safely come up to a normal operating temperature. Once the computer senses that the engine is up to normal operating temps, the idle will gradually drop to a lower RPM.

    Try this when you have about five minutes extra on a cold day:

    Get in your car, but do not touch any pedals. Turn off the A/C and heater, and the stereo. Start your car making sure to either watch the RPM gauge or listen to the engine. Watch or listen to the car's engine speed. You should notice that it starts off high, but in a minute or two will drop down until it is at a normal even speed. Your car is now warmed up.

    It was only necessary to turn off the items listed above so that you could pay attention to the engine. You do not need to do this every time you start your car.

    I hope this clears up the confusion for you. Letting your car warm up properly will keep your car happy, and has the added bonus of helping your car last just a bit longer. Good luck!

    Source(s): Life experience, and over 20 years spent wrenching on old cars and trucks.
  • kdog
    Lv 4
    1 decade ago

    The cat converter has nothing to do with it. They don't magically make the car run better when it is cold. Oil doesn't lubricate as well when it is cold. You should let it run for a few seconds so the oil has time to circulate, then drive slowly for a the first few minutes to let the oil warm up and protect everything properly.

  • ?
    Lv 4
    4 years ago

    that's not honestly mandatory to warmth your automobile earlier using. It comes all the way down to non-public decision. using your automobile slowly for some blocks is assistance to warmth the motorcar. allowing the motorcar to idle in the driveway no longer in undemanding words wastes gas in spite of the undeniable fact that it will strengthen the probabilities for motorcar robbery. in spite of the undeniable fact that, in truly chilly climates, the position the lows may reason engines to freeze, that's a sturdy practice to finish that. Or more beneficial useful yet, purchase and use an engine block heater. That being suggested, i visit't imagine of everywhere in the continental US the position the temperatures are so consistenly low adequate to endanger a chance of engine block damage or ward off you from commencing the motorcar. This in undemanding words occurs at the same time as the motorcar has no longer been pushed for weeks at a time. in case you insist on warming the motorcar up, it in undemanding words favor to be finished see you later because it takes for the engine to idle at its ordinary %. desire this helps.

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  • 1 decade ago

    Cars do not need to warm up like they did years ago. Under a minute is sufficient. Anything longer than that is just for personal comfort, or to clear the windows of frost or ice. But then, that's what scrapers are for.

  • 1 decade ago

    Warm up til car idles down.

  • 1 decade ago

    I've read that somewhere. I never warm my cars up, even in winter.

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