The Importance of Warming Your Vehicle Even when it's cold outside, modern
engines don't stay cold inside for very long. A wise man once said you can't
teach old habit new tricks before it dies hard. Or something along those lines.
In the early days of the automobile, owners did well to get their cars running
after a dozen attempts, and keeps it running for as many minutes -- and that was
on the best of days. Times have changed quite a bit since then, and so have the
ways we maintain and drive our cars. Have a question? Get an answer from a
mechanic now!Basic Warming Back when even the best cars on the road ran on
metered fuel leaks -- aka"carburetors"-- automobiles had a difficult time
running while cold. Engines are designed to run at a certain temperature,
usually around the boiling point of water. Much above or below that temperature,
and the engine loses combustion efficiency and fails to turn the fuel going in
into horsepower. Carburetors got around this problem using a choke, which
limited airflow and proportionately increased the amount of fuel in the mix. The
choke had to stay closed until the car warmed up and combustion efficiency came
back up to level. By that time, the engine's metal had expanded to where it
needed to be, and all the fluids were warm and circulating Autel
Autolink AL609. Unfortunately, carbureted cars were often so cantankerous
during the warm-up period that they were all but undriveable for several minutes
-- hence, the need for a considerable warm-up period before setting Converter
Light-Off Prior to catalytic converters, few people really thought about warm-up
procedures provided that the car eventually warmed up while idling. However,
things changed drastically from the factory perspective when cats debuted. A
catalytic converter works like a chemically enhanced furnace, burning off
unburned fuel before it escapes from the exhaust pipe. To do that, the converter
matrix has to reach a certain temperature -- usually about 800 degrees
Fahrenheit. So, give
your car 30 seconds under most circumstances, perhaps as much as a minute if
you're starting out with 0 degree temperatures, and then slowly set off. Drive
easily for the first few miles to give your transmission, drivetrain and
suspension components time to come up to temperature. It's a myth that idling is
the best way to warm a car anyway. Engines produce more heat under load, so the
quickest way to get your engine up to temperature -- and your heater working, if
need be -- is to drive the car. That goes for cat light-off too; the converter
will light off more quickly while the engine is under load than it will when
idling. Try to running your own test sometimes. Record how long it takes your
engine to reach operating temperature from dead cold after a 30-second warm-up
and gentle drive autel md802, vs just
leaving it idling in your driveway.
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